CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Assets:
Cash	$ 19,753	$ 56,363
Accounts receivable	347	426
Income tax receivable - Note 15	95	0
Inventories - Note 4	16,833	12,867
Ore on leach pads - Note 4	29,588	38,041
Prepaids and other, net - Note 5	5,666	4,303
Current assets	72,282	112,000
Ore on leach pads - Note 4	6,142	7,243
Plant, equipment, and mine development, net - Note 6	69,777	60,223
Restricted cash - Note 7	34,293	39,677
Other assets - Note 5	12,838	13,483
Total assets	195,332	232,626
Liabilities:
Accounts payable and accrued expenses	10,852	12,280
Deferred revenue - Note 13	1,598	0
Debt, net - Note 9	12,745	5,120
Deferred gain on sale of royalty - Note 10	125	124
Other liabilities - Note 8	5,847	4,157
Current liabilities	31,167	21,681
Warrant liabilities - Note 11	4,149	15,389
Debt, net - Note 9	146,189	142,665
Deferred gain on sale of royalty - Note 10	29,714	29,839
Asset retirement obligation - Note 12	5,091	4,785
Other liabilities - Note 8	541	1,650
Total liabilities	216,851	216,009
Commitments and contingencies - Note 20
Stockholders' (deficit) equity
Common stock, $0.0001 par value; 400,000,000 shares authorized; 60,410,922 issued and outstanding at September 30, 2021; and 59,901,306 issued and outstanding at December 31, 2020	6	6
Additional paid-in capital	540,562	537,370
Accumulated deficit	(562,087)	(520,759)
Total stockholders' (deficit) equity	(21,519)	16,617
Total liabilities and stockholders' (deficit) equity	$ 195,332	$ 232,626