Inventories

3 Months Ended

Mar. 31, 2021

Inventory Disclosure [Abstract]

Inventories

Inventories

The major components of inventories were as follows:

	March 31, 2021		December 31, 2020
Petroleum products	$	2,584	$	5,840
Crude oil	14,633		37,661
Caustic soda	5,108		5,167
NaHS	7,736		9,101
Raw materials - Alkali operations	6,492		7,120
Work-in-process - Alkali operations	10,700		9,355
Finished goods, net - Alkali operations	11,988		13,002
Materials and supplies, net - Alkali operations	13,186		12,631
Total	$	72,427	$	99,877

    Inventories are valued at the lower of cost or net realizable value. The net realizable value of inventories were recorded below cost by $0.4 million and $5.0 million as of March 31, 2021 and December 31, 2020, respectively, therefore we reduced the value of our inventory in our Unaudited Consolidated Financial Statements by these amounts.

Materials and supplies include chemicals, maintenance supplies, and spare parts which will be consumed in the mining of trona ore and production of soda ash processes.