<SEC-DOCUMENT>0001104659-24-103776.txt : 20240927
<SEC-HEADER>0001104659-24-103776.hdr.sgml : 20240927
<ACCEPTANCE-DATETIME>20240927171208
ACCESSION NUMBER:		0001104659-24-103776
CONFORMED SUBMISSION TYPE:	SD
PUBLIC DOCUMENT COUNT:		12
<RULE>
<RULE-NAME>13q-1
<ITEM>
<ITEM-NUMBER>2.01
<ITEM-PERIOD>20231231
</ITEM>
</RULE>
<RESOURCE-EXT-ISSUER>N
FILED AS OF DATE:		20240927
DATE AS OF CHANGE:		20240927

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CENTURY ALUMINUM CO
		CENTRAL INDEX KEY:			0000949157
		STANDARD INDUSTRIAL CLASSIFICATION:	PRIMARY PRODUCTION OF ALUMINUM [3334]
		ORGANIZATION NAME:           	04 Manufacturing
		IRS NUMBER:				133070826
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SD
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34474
		FILM NUMBER:		241335941

	BUSINESS ADDRESS:	
		STREET 1:		1 SOUTH WACKER DRIVE
		STREET 2:		SUITE 1000
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60606
		BUSINESS PHONE:		3126963101

	MAIL ADDRESS:	
		STREET 1:		1 SOUTH WACKER DRIVE
		STREET 2:		SUITE 1000
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60606
</SEC-HEADER>
<DOCUMENT>
<TYPE>SD
<SEQUENCE>1
<FILENAME>cenx-20231231xsd.htm
<DESCRIPTION>FORM SD
<TEXT>
<!--Enhanced HTML document created with Toppan Merrill Bridge  10.6.125.0--><!--Created on: 9/27/2024 08:33:31 PM (UTC)--><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"><html><head><meta charset="UTF-8"><title></title></head><body><div style="margin-top:30pt;"></div><div style="max-width:100%;padding-left:5.88%;padding-right:5.88%;position:relative;"><div style="clear:both;max-width:100%;position:relative;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;padding-bottom:1pt;padding-top:1pt;border-bottom:1px solid #000000;border-top:3.0pt solid #000000;margin:0pt;"><font style="font-size:1pt;visibility:hidden;">&#8203;</font></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><font style="visibility:hidden;">&#8203;</font></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt;"><b style="font-size:16pt;font-weight:bold;">UNITED STATES</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt;"><b style="font-size:16pt;font-weight:bold;">SECURITIES AND EXCHANGE COMMISSION</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt 0pt 24pt 0pt;"><b style="font-weight:bold;">WASHINGTON, D.C. 20549</b></p><div align="left"><table style="border-collapse:collapse;font-size:16pt;height:max-content;width:100%;"><tr style="height:27pt;"><td style="vertical-align:bottom;width:100%;border-bottom:1px solid #000000;border-top:1px solid #000000;margin:0pt;padding:0pt;"><div style="height:27pt;overflow:hidden;overflow-wrap:break-word;position:relative;"><div style="bottom:0pt;position:absolute;width:100%;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt 0pt 1.5pt 0pt;"><b style="font-size:14pt;font-weight:bold;">FORM SD</b></p></div></div></td></tr></table></div><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt 0pt 6pt 0pt;"><font style="visibility:hidden;">&#8203;</font></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt 0pt 6pt 0pt;"><b style="font-size:12pt;font-weight:bold;">SPECIALIZED DISCLOSURE REPORT</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;padding-bottom:1pt;text-align:center;border-bottom:1px solid #000000;margin:0pt;"><font style="visibility:hidden;">&#8203;</font></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><font style="visibility:hidden;">&#8203;</font></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt;"><b style="font-size:14pt;font-weight:bold;">Century Aluminum Company</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt 0pt 6pt 0pt;">(Exact name of registrant as specified in its charter)</p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><font style="visibility:hidden;">&#8203;</font></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><font style="visibility:hidden;">&#8203;</font></p><div align="left"><table style="border-collapse:collapse;font-size:16pt;height:max-content;width:100%;"><tr><td style="vertical-align:top;width:33.33%;border-top:1px solid #000000;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt 0pt 1pt 0pt;"><b style="font-weight:bold;">Delaware</b></p></td><td style="vertical-align:top;width:33.34%;border-top:1px solid #000000;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt 0pt 1pt 0pt;"><b style="font-weight:bold;">001-34474</b></p></td><td style="vertical-align:top;width:33.32%;border-top:1px solid #000000;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt 0pt 1pt 0pt;"><b style="font-weight:bold;">13-3070826</b></p></td></tr><tr><td style="vertical-align:top;width:33.33%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:8pt;text-align:center;margin:0pt 0pt 1pt 0pt;">(State or other jurisdiction of incorporation)</p></td><td style="vertical-align:top;width:33.34%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:8pt;text-align:center;margin:0pt 0pt 1pt 0pt;">(Commission File Number)</p></td><td style="vertical-align:top;width:33.32%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:8pt;text-align:center;margin:0pt 0pt 1pt 0pt;">(I.R.S. Employer Identification No.)</p></td></tr></table></div><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><font style="visibility:hidden;">&#8203;</font></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt;"><b style="font-weight:bold;">One South Wacker Drive</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt;"><b style="font-weight:bold;">Suite 1000</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt;"><b style="font-weight:bold;">Chicago</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt;"><b style="font-weight:bold;white-space:pre-wrap;">Illinois  60606</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt 0pt 10pt 0pt;"><font style="white-space:pre-wrap;"> (Address of principal executive offices)</font></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt;"><b style="font-weight:bold;">John DeZee</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt;"><b style="font-weight:bold;">(312) 696-3101</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt 0pt 12pt 0pt;">(Name and telephone number, including area code, of the person to contact in connection with this report)</p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;margin:0pt 0pt 12pt 0pt;">Check the appropriate box to indicate the rule pursuant to which this Form is being submitted, and provide the period to which the information in this Form applies:</p><p style="font-family:'Times New Roman','Times','serif';font-size:9pt;text-align:justify;margin:0pt 0pt 12pt 0pt;"><font style="font-family:'Segoe UI Symbol';">&#9744;</font><font style="font-size:10pt;"> Rule 13p-1 under the Securities Exchange Act (17 CFR 240.13p-1) for the reporting period from January&#160;1 to December&#160;31, _____.</font></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;margin:0pt 0pt 12pt 0pt;"><font style="font-family:'Segoe UI Symbol';">&#9746;</font> Rule 13q-1 under the Securities Exchange Act (17 CFR 240.13q-1) for the fiscal year ended December&#160;31, 2023</p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;padding-bottom:1pt;padding-top:1pt;border-bottom:3.0pt solid #000000;border-top:1px solid #000000;margin:0pt;"><font style="font-size:1pt;visibility:hidden;">&#8203;</font></p><p style="display:none;font-family:'Times New Roman','Times','serif';line-height:0pt;margin:0pt;"><font style="font-size:0pt;visibility:hidden;">&#8203;</font></p></div></div><hr style="background-color:#000000;clear:both;color:#000000;height:2pt;line-height:0;margin-bottom:30pt;margin-left:5.88%;margin-right:5.88%;margin-top:30pt;page-break-after:always;width:88.24%;border-width:0;"><div style="max-width:100%;padding-left:5.88%;padding-right:5.88%;position:relative;"><div style="clear:both;max-width:100%;position:relative;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;margin:0pt 0pt 12pt 0pt;"><b style="font-weight:bold;">Section&#160;1 - Conflict Minerals Disclosure</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;margin:0pt 0pt 12pt 0pt;"><b style="font-weight:bold;">Item 1.01 Conflict Minerals Disclosure and Report</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;margin:0pt 0pt 12pt 0pt;">Not applicable.</p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;margin:0pt 0pt 12pt 0pt;"><b style="font-weight:bold;">Item 1.02 Exhibit</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;margin:0pt 0pt 12pt 0pt;">Not applicable.</p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;margin:0pt 0pt 12pt 0pt;"><b style="font-weight:bold;">Section&#160;2 - Resource Extraction Issuer Disclosure</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;margin:0pt 0pt 12pt 0pt;"><b style="font-weight:bold;">Item 2.01 Resource Extraction Issuer Disclosure and Report</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;margin:0pt 0pt 12pt 0pt;">On May&#160;2, 2023, the registrant&#8217;s wholly-owned subsidiary, Century Aluminum Jamaica Holdings, Inc., completed the acquisition of all the outstanding share capital of General Alumina Holdings Limited, the holder of a 55% interest in Jamalco JV (&#8220;Jamalco&#8221;), an unincorporated joint venture engaged in bauxite mining and alumina production in Jamaica. &#160;Pursuant to Item 2.01(b)(2) of Form SD, the registrant will not commence reporting the information required under Rule 13q-1 until the submission of its Form SD for the fiscal year ended December&#160;31, 2024.</p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;margin:0pt 0pt 12pt 0pt;"><b style="font-weight:bold;">Section&#160;3 - Exhibits</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;margin:0pt 0pt 12pt 0pt;"><b style="font-weight:bold;">Item 3.01 Exhibits</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;margin:0pt 0pt 12pt 0pt;">Not applicable.</p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;margin:0pt 0pt 12pt 0pt;">The following exhibit is filed as part of this report:</p><div align="left"><table style="border-collapse:collapse;font-size:16pt;height:max-content;width:100%;"><tr style="height:1pt;"><td style="vertical-align:bottom;width:15.62%;margin:0pt;padding:0pt;"><div style="height:1pt;overflow:hidden;overflow-wrap:break-word;position:relative;"><div style="bottom:0pt;position:absolute;width:100%;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><font style="display:inline-block;text-indent:0pt;width:36pt;"></font><font style="font-size:1pt;visibility:hidden;">&#8203;</font></p></div></div></td><td style="vertical-align:bottom;width:2.84%;margin:0pt;padding:0pt;"><div style="height:1pt;overflow:hidden;overflow-wrap:break-word;position:relative;"><div style="bottom:0pt;position:absolute;width:100%;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><font style="font-size:1pt;visibility:hidden;">&#8203;</font></p></div></div></td><td style="vertical-align:bottom;width:81.53%;margin:0pt;padding:0pt;"><div style="height:1pt;overflow:hidden;overflow-wrap:break-word;position:relative;"><div style="bottom:0pt;position:absolute;width:100%;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><font style="font-size:1pt;visibility:hidden;">&#8203;</font></p></div></div></td></tr><tr style="height:14.25pt;"><td style="vertical-align:bottom;width:15.62%;border-bottom:1px solid #000000;margin:0pt;padding:0pt;"><div style="height:14.25pt;overflow:hidden;overflow-wrap:break-word;position:relative;"><div style="bottom:0pt;position:absolute;width:100%;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt 0pt 1.5pt 0pt;">Exhibit Number</p></div></div></td><td style="vertical-align:bottom;width:2.84%;margin:0pt;padding:0pt;"><div style="height:14.25pt;overflow:hidden;overflow-wrap:break-word;position:relative;"><div style="bottom:0pt;position:absolute;width:100%;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt 0pt 1.5pt 0pt;">&#160;&#160;&#160;&#160;</p></div></div></td><td style="vertical-align:bottom;width:81.53%;border-bottom:1px solid #000000;margin:0pt;padding:0pt;"><div style="height:14.25pt;overflow:hidden;overflow-wrap:break-word;position:relative;"><div style="bottom:0pt;position:absolute;width:100%;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt 0pt 1.5pt 0pt;">Description</p></div></div></td></tr><tr style="height:14.4pt;"><td style="vertical-align:bottom;width:15.62%;border-top:1px solid #000000;margin:0pt;padding:0pt;"><div style="height:14.4pt;overflow:hidden;overflow-wrap:break-word;position:relative;"><div style="bottom:0pt;position:absolute;width:100%;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt 0pt 1.5pt 0pt;">99.1</p></div></div></td><td style="vertical-align:bottom;width:2.84%;margin:0pt;padding:0pt;"><div style="height:14.4pt;overflow:hidden;overflow-wrap:break-word;position:relative;"><div style="bottom:0pt;position:absolute;width:100%;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt 0pt 1.5pt 0pt;"><font style="visibility:hidden;">&#8203;</font></p></div></div></td><td style="vertical-align:bottom;width:81.53%;border-top:1px solid #000000;margin:0pt;padding:0pt;"><div style="height:14.4pt;overflow:hidden;overflow-wrap:break-word;position:relative;"><div style="bottom:0pt;position:absolute;width:100%;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt 0pt 1.5pt 0pt;"><a style="font-family:&quot;'Times New Roman','Times','serif'&quot;;" href="cenx-20231231xex99d1.htm"><font style="font-family:'Times New Roman','Times','serif';font-style:normal;font-weight:normal;">Resource Extraction Payment Report as required by Item 2.01 of this Form.</font></a></p></div></div></td></tr></table></div><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><font style="visibility:hidden;">&#8203;</font></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><font style="font-size:1pt;visibility:hidden;">&#8203;</font></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><font style="visibility:hidden;">&#8203;</font></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><font style="visibility:hidden;">&#8203;</font></p></div></div><hr style="background-color:#000000;clear:both;color:#000000;height:2pt;line-height:0;margin-bottom:30pt;margin-left:5.88%;margin-right:5.88%;margin-top:30pt;page-break-after:always;width:88.24%;border-width:0;"><div style="max-width:100%;padding-left:5.88%;padding-right:5.88%;position:relative;"><div style="clear:both;max-width:100%;position:relative;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt 0pt 10pt 0pt;"><b style="font-weight:bold;">SIGNATURES</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;text-indent:36pt;margin:0pt 0pt 10pt 0pt;">Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.</p><div><table style="border-collapse:collapse;font-size:16pt;height:max-content;margin-left:auto;margin-right:auto;padding-left:0pt;padding-right:0pt;width:100%;" align="center"><tr><td style="vertical-align:bottom;white-space:nowrap;width:42.5%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><font style="visibility:hidden;">&#8203;</font></p></td><td colspan="3" style="vertical-align:bottom;width:57.5%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><b style="font-weight:bold;">CENTURY ALUMINUM COMPANY</b></p></td></tr><tr><td style="vertical-align:bottom;white-space:nowrap;width:42.5%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><font style="visibility:hidden;">&#8203;</font></p></td><td style="vertical-align:bottom;width:3.25%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><font style="visibility:hidden;">&#8203;</font></p></td><td colspan="2" style="vertical-align:bottom;width:54.24%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><font style="font-style:italic;visibility:hidden;">&#8203;</font></p></td></tr><tr><td style="vertical-align:bottom;white-space:nowrap;width:42.5%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;">Date: September 27, 2024</p></td><td style="vertical-align:bottom;width:3.25%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;">By:</p></td><td colspan="2" style="vertical-align:bottom;width:54.24%;border-bottom:1px solid #000000;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><i style="font-style:italic;">/s/ John DeZee</i></p></td></tr><tr><td style="vertical-align:bottom;white-space:nowrap;width:42.5%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><font style="visibility:hidden;">&#8203;</font></p></td><td style="vertical-align:bottom;width:3.25%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><font style="visibility:hidden;">&#8203;</font></p></td><td style="vertical-align:bottom;width:5.41%;border-top:1px solid #000000;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;">Name:</p></td><td style="vertical-align:bottom;width:48.82%;border-top:1px solid #000000;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;">John DeZee</p></td></tr><tr><td style="vertical-align:bottom;white-space:nowrap;width:42.5%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><font style="visibility:hidden;">&#8203;</font></p></td><td style="vertical-align:bottom;width:3.25%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><font style="visibility:hidden;">&#8203;</font></p></td><td style="vertical-align:bottom;width:5.41%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;">Title:</p></td><td style="vertical-align:bottom;width:48.82%;margin:0pt;padding:0pt;"><p style="font-family:'Times New 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<DESCRIPTION>EXHIBIT-99.1
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<!--Enhanced HTML document created with Toppan Merrill Bridge  10.6.125.0--><!--Created on: 9/27/2024 08:33:31 PM (UTC)--><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"><html><head><meta charset="UTF-8"><title></title></head><body><div style="margin-top:30pt;"></div><div style="max-width:100%;padding-left:5.88%;padding-right:5.88%;position:relative;"><div style="clear:both;max-width:100%;position:relative;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:right;margin:0pt 0pt 12pt 0pt;"><b style="font-weight:bold;">Exhibit 99.1</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt 0pt 12pt 0pt;"><b style="font-weight:bold;">Resource Extraction Payment Report</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;margin:0pt 0pt 12pt 0pt;">As disclosed under Item&#160;2.01, on May&#160;2, 2023, the registrant&#8217;s wholly-owned subsidiary, Century Aluminum Jamaica Holdings, Inc., completed the acquisition of all the outstanding share capital of General Alumina Holdings Limited, the holder of a 55% interest in Jamalco JV (&#8220;Jamalco&#8221;), an unincorporated joint venture engaged in bauxite mining and alumina production in Jamaica. &#160;Pursuant to Item 2.01(b)(2) of Form SD, the registrant will not commence reporting the information required under Rule 13q-1 until the submission of its Form SD for the fiscal year ended December&#160;31, 2024.</p></div></div><hr style="background-color:#000000;clear:both;color:#000000;height:2pt;line-height:0;margin-left:5.88%;margin-right:5.88%;margin-top:30pt;page-break-after:avoid;width:88.24%;border-width:0;"></body></html>
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<DESCRIPTION>IDEA: XBRL DOCUMENT
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<title></title>
<link rel="stylesheet" type="text/css" href="include/report.css">
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<body>
<span style="display: none;">v3.24.3</span><table class="report" border="0" cellspacing="2" id="idm46262706437984">
<tr>
<th class="tl" colspan="1" rowspan="2"><div style="width: 200px;"><strong>Document Information<br></strong></div></th>
<th class="th" colspan="1">12 Months Ended</th>
</tr>
<tr><th class="th"><div>Dec. 31, 2023</div></th></tr>
<tr class="re">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_DocumentInformationLineItems', window );"><strong>Document Information:</strong></a></td>
<td class="text">&#160;<span></span>
</td>
</tr>
<tr class="ro">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_DocumentType', window );">Document Type</a></td>
<td class="text">2.01 SD<span></span>
</td>
</tr>
<tr class="re">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_AmendmentFlag', window );">Amendment</a></td>
<td class="text">false<span></span>
</td>
</tr>
<tr class="ro">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_EntityCentralIndexKey', window );">CIK</a></td>
<td class="text">0000949157<span></span>
</td>
</tr>
<tr class="re">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_EntityRegistrantName', window );">Registrant Name</a></td>
<td class="text">Century Aluminum Company<span></span>
</td>
</tr>
<tr class="ro">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_DocumentPeriodEndDate', window );">Period End Date</a></td>
<td class="text">Dec. 31,  2023<span></span>
</td>
</tr>
<tr class="re">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_dei_EntityReportingCurrencyISOCode', window );">Reporting Currency</a></td>
<td class="text">USD<span></span>
</td>
</tr>
</table>
<div style="display: none;">
<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_AmendmentFlag">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Boolean flag that is true when the XBRL content amends previously-filed or accepted submission.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>No definition available.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_AmendmentFlag</td>
</tr>
<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
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<tr>
<td><strong> Data Type:</strong></td>
<td>xbrli:booleanItemType</td>
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<td><strong> Balance Type:</strong></td>
<td>na</td>
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<td><strong> Period Type:</strong></td>
<td>duration</td>
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</table></div>
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<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_DocumentInformationLineItems">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>No definition available.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_DocumentInformationLineItems</td>
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<tr>
<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
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<td>xbrli:stringItemType</td>
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<td>na</td>
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<td><strong> Period Type:</strong></td>
<td>duration</td>
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</table></div>
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<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_DocumentPeriodEndDate">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>For the EDGAR submission types of Form 8-K: the date of the report, the date of the earliest event reported; for the EDGAR submission types of Form N-1A: the filing date; for all other submission types: the end of the reporting or transition period. The format of the date is YYYY-MM-DD.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>No definition available.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_DocumentPeriodEndDate</td>
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<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
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<td><strong> Data Type:</strong></td>
<td>xbrli:dateItemType</td>
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<td><strong> Balance Type:</strong></td>
<td>na</td>
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<tr>
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<td>duration</td>
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<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_DocumentType">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>No definition available.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_DocumentType</td>
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<td style="padding-right: 4px;white-space:nowrap;"><strong> Namespace Prefix:</strong></td>
<td>dei_</td>
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<td><strong> Data Type:</strong></td>
<td>dei:submissionTypeItemType</td>
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<td><strong> Balance Type:</strong></td>
<td>na</td>
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<td><strong> Period Type:</strong></td>
<td>duration</td>
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</table></div>
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<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_EntityCentralIndexKey">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>Reference 1: http://www.xbrl.org/2003/role/presentationRef<br> -Publisher SEC<br> -Name Exchange Act<br> -Number 240<br> -Section 12<br> -Subsection b-2<br></p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_EntityCentralIndexKey</td>
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<td><strong> Balance Type:</strong></td>
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<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_EntityRegistrantName">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>Reference 1: http://www.xbrl.org/2003/role/presentationRef<br> -Publisher SEC<br> -Name Exchange Act<br> -Number 240<br> -Section 12<br> -Subsection b-2<br></p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_EntityRegistrantName</td>
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<td>dei_</td>
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<td><strong> Data Type:</strong></td>
<td>xbrli:normalizedStringItemType</td>
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<td><strong> Balance Type:</strong></td>
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<td><strong> Period Type:</strong></td>
<td>duration</td>
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<table border="0" cellpadding="0" cellspacing="0" class="authRefData" style="display: none;" id="defref_dei_EntityReportingCurrencyISOCode">
<tr><td class="hide"><a style="color: white;" href="javascript:void(0);" onclick="Show.hideAR();">X</a></td></tr>
<tr><td><div class="body" style="padding: 2px;">
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">- Definition</a><div><p>The three character ISO 4217 code for the currency used for reporting purposes. Example: 'USD'.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ References</a><div style="display: none;"><p>No definition available.</p></div>
<a href="javascript:void(0);" onclick="Show.toggleNext( this );">+ Details</a><div style="display: none;"><table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><strong> Name:</strong></td>
<td style="white-space:nowrap;">dei_EntityReportingCurrencyISOCode</td>
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<td>dei:currencyItemType</td>
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<td><strong> Balance Type:</strong></td>
<td>na</td>
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<td><strong> Period Type:</strong></td>
<td>duration</td>
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<head>
<title></title>
<link rel="stylesheet" type="text/css" href="include/report.css">
<script type="text/javascript" src="Show.js">/* Do Not Remove This Comment */</script><script type="text/javascript">
							function toggleNextSibling (e) {
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							e.nextSibling.style.display='block';
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</head>
<body>
<span style="display: none;">v3.24.3</span><table class="report" border="0" cellspacing="2" id="idm46262706452944">
<tr>
<th class="tl" colspan="1" rowspan="1"><div style="width: 200px;"><strong>Payments, by Category<br></strong></div></th>
<th class="th">
<div>Total Payments </div>
<div>USD ($)</div>
</th>
</tr>
<tr class="re">
<td class="pl" style="border-bottom: 0px;" valign="top"><a class="a" href="javascript:void(0);" onclick="Show.showAR( this, 'defref_=', window );">Total</a></td>
<td class="nump">$ 0<span></span>
</td>
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<div style="display: none;"></div>
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<span style="display: none;">v3.24.3</span><table class="report" border="0" cellspacing="2" id="idm46262706435840">
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<th class="tl" colspan="1" rowspan="1"><div style="width: 200px;"><strong>Payments, by Project<br></strong></div></th>
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<span style="display: none;">v3.24.3</span><table class="report" border="0" cellspacing="2" id="idm46262706454736">
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<th class="tl" colspan="1" rowspan="1"><div style="width: 200px;"><strong>Payments, by Government<br></strong></div></th>
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