Note 2 - Long-lived Asset Impairments	12 Months Ended
Dec. 31, 2021
Notes to Financial Statements
Asset Impairment Charges [Text Block]	(2) LONG-LIVED ASSET IMPAIRMENTS Long-lived assets are reviewed for impairment whenever events or changes in circumstance indicate that the carrying amount of the assets may not be recoverable. The impact of COVID-19 is being monitored closely, but for the years ended December 31, 2021 and 2020, there were no material COVID-19 related impairment charges recorded for long-lived assets. Prosperity Mine We recorded an impairment of $1.6 million as of December 31, 2021 on assets consisting of the wash plant and rail facilities at the Prosperity Mine. The wash plant was torn down and the remaining rail was pulled up in the fourth quarter of 2021. We have estimated the scrap value to be $1.1 million on the carrying value of $2.7 million. The remaining scrap will be sold in 2022. Hourglass Sands We recorded an impairment of $2.9 million as of December 31, 2019, due to softness in the pricing of the frac sand market. The impairment included inventory, land, mine development, buildings and equipment and was determined using a market approach. The remaining fair market value of inventory, equipment, and buildings at Hourglass Sands was $1.9 million as of December 31, 2019. Due to the continued regression of the frac sand market, in August 2020, we ceased operations of the plant and recorded an impairment of $1.8 million in the third quarter of 2020, which included the remaining inventory and buildings and which was determined using a market approach.

Note 2 - Long-lived Asset Impairments

12 Months Ended

Dec. 31, 2021

(2) LONG-LIVED ASSET IMPAIRMENTS

Long-lived assets are reviewed for impairment whenever events or changes in circumstance indicate that the carrying amount of the assets may not be recoverable. The impact of COVID-19 is being monitored closely, but for the years ended December 31, 2021 and 2020, there were no material COVID-19 related impairment charges recorded for long-lived assets.

Prosperity Mine

We recorded an impairment of $1.6 million as of December 31, 2021 on assets consisting of the wash plant and rail facilities at the Prosperity Mine. The wash plant was torn down and the remaining rail was pulled up in the fourth quarter of 2021. We have estimated the scrap value to be $1.1 million on the carrying value of $2.7 million. The remaining scrap will be sold in 2022.

Hourglass Sands

We recorded an impairment of $2.9 million as of December 31, 2019, due to softness in the pricing of the frac sand market. The impairment included inventory, land, mine development, buildings and equipment and was determined using a market approach. The remaining fair market value of inventory, equipment, and buildings at Hourglass Sands was $1.9 million as of December 31, 2019. Due to the continued regression of the frac sand market, in August 2020, we ceased operations of the plant and recorded an impairment of $1.8 million in the third quarter of 2020, which included the remaining inventory and buildings and which was determined using a market approach.