MAMMOTH REPORTS AN ADDITIONAL TWO KILOMETRES OF 3D GEOPHYSICAL MODELLING AT ITS TENORIBA GOLD-SILVER PROPERTY, MEXICO

Toronto, Canada (April 22, 2021) – Mammoth Resources Corp. (TSX-V: MTH), (the “Company”, or “Mammoth”) is pleased to provide results from an additional two kilometres (km) of the 3-dimensional (3D) drill target modelling from its infill, Induced Polarization/Magnetometer (IP/Mag) geophysical survey recently completed at its 100% owned Tenoriba gold-silver property located in the prolific Sierra Madre precious metal belt, Mexico. This 3D modelling shows strong correlation between anomalous surface gold-in-soil, chip and channel samples together with numerous gold intervals in diamond drilling and extends these coincident features over what now totals a 2.4 km trend of a larger 6 km trend of surface gold-silver mineralization at Tenoriba.

Colibri Partner Chooses Layne de Mexico to Drill 2,000 Metres at El Mezquite Gold and Silver Project in Sonora

Dieppe, New Brunswick–(Newsfile Corp. – April 22, 2021) – Colibri Resource Corporation (TSXV: CBI) (“Colibri” or the “Company”) is very pleased announce that its partner Silver Spruce Resources has awarded the drilling contract for El Mezquite Gold & Silver Project to Layne de Mexico. Mobilization of the reverse circulation (RC) rig and geological team to the Property is planned during the first week of May. Silver Spruce reports that they intend to drill 2,000 metres in up to 14 holes in the first ever drilling program to take place at the project.

KOOTENAY PROVIDES UPDATE ON ONGOING DRILL PROGRAM AT COPALITO SILVER-GOLD PROJECT, MEXICO

Kootenay Silver Inc. (TSXV: KTN) (the “Company” or “Kootenay”) is pleased to announce that drilling is proceeding as scheduled at the Copalito silver-gold project, located in Sinaloa State, Mexico. To date, the Company has completed 1,600 of the planned 3,500 meters (the “Program”) over 19 shallow drill holes, ranging from 50 to 160 meters in depth. As previously announced in the Company’s new release related to Columba property dated April 15, 2021, laboratory delays for assay turn around time has been longer than expected causing result announcement delays.

SIERRA METALS TO INVEST US$28 MILLION FOR AN IRON ORE PROCESSING PLANT EXPECTED TO PRODUCE APPROXIMATELY 500,000 TONNES PER YEAR OF MAGNETITE CONCENTRATE AT THE BOLIVAR MINE, MEXICO

TORONTO–(BUSINESS WIRE)– Sierra Metals Inc. (TSX: SMT) (BVL: SMT) (NYSE AMERICAN: SMTS) (“Sierra Metals” or “the Company”) today announces that its Board of Directors has approved the investment by the Company of US$28 million for the construction of a magnetite processing plant including an initial expenditure of $5.2 million for early procurement and contracting on the project. The plant is expected to produce approximately 500,000 tonnes per year of 62% iron ore fines concentrate at the Company’s Bolivar Mine located in the Chihuahua State, Mexico.