CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Income Statement [Abstract]
Revenue		$ 47,127	$ 0	$ 47,127	$ 0
Costs of sales		23,363	0	23,363	0
Gross profit		23,764	0	23,764	0
Exploration and mine development costs		471	434	1,668	1,485
Selling, general, and administrative expenses		11,185	7,160	31,793	20,200
Total operating expenses		11,656	7,594	33,461	21,685
Income (loss) from equity method investments	[1]	3,852	(2,003)	(1,565)	(6,547)
Income (loss) from operations		15,960	(9,597)	(11,262)	(28,232)
Interest income		1,031	373	2,959	373
Interest expense		(8)	(21)	(34)	(97)
Loss from foreign currency exchange		(22)	(35)	(88)	(60)
Gain on dilution of equity method investments	[1]	7,958	29,367	15,208	29,367
Total other income		8,959	29,684	18,045	29,583
Income before taxes		24,919	20,087	6,783	1,351
Income tax expense		2,028	3,422	3,170	3,422
Net income (loss)		$ 22,891	$ 16,665	$ 3,613	$ (2,071)
Earnings (loss) per share:
Basic (in dollars per share)		$ 1.19	$ 0.93	$ 0.19	$ (0.12)
Diluted (in dollars per share)		$ 1.19	$ 0.92	$ 0.19	$ (0.12)
Weighted-average shares outstanding
Basic (in shares)		19,203	17,966	18,974	17,343
Diluted (in shares)		19,239	18,081	19,011	17,343

[1] Income (loss) from equity method investments and Gain on dilution of equity method investments are reported on a one-quarter lag.