Diamond Drilling Completed At The Aries Gold Prospect

Drill program is co-funded by the Western Australian Government through the Exploration Incentive Scheme (EIS).

Limited diamond drilling by previous explorers returned intercepts of:

12m @ 4.51 g/t Au from 201m (SXD 544)

5.65m @ 3.07 g/t Au from 341m (SXD 546)

VANCOUVER,BC,July 5,2021 -- Altan Rio Minerals Limited (TSXV: AMO) ("Altan Rio" or the "Company") is pleased to announce a two-hole drilling program has been completed at the Aries prospect within the Southern Cross North Project ("SCNP") in Western Australia.

No exploration has been undertaken at Aries since 2005,where previous explorers had identified a 1 kilometre x 400 metre gold in bedrock gold anomaly (> 0.1 g/t Au) beneath a 90 metre thick recent sediment sequence.

Importantly,the Aries prospect is some 1.6 kilometres north of the Golden Pig Open Pit and some 750 metres north of the underground development where combined mining operations up to closure in 2005 had recorded production of 2.66Mt @ 5.88g/t for 502,119oz Au(refer TSXV: AMO N43-101 Report).

Between 2004 and 2005,five diamond holes were completed at Aries to evaluate the bedrock gold anomaly with significant results recorded including 12m @ 4.51g/t Au from 201m in drillhole SXD544 and 5.65m @ 3.07 g/t Au from 341m in drillhole SXD546.

These historical intercepts are considered similar to the mineralisation style observed at the Golden Pig Operations which was described as intense quartz and calc-silicate veining with pyrrhotite and chalcopyrite dominated sulphides within a sheared Ultramafic and Banded Iron Formation (BIF) stratigraphic package.

In May 2020,Altan Rio was awarded funding under the West Australian Government's Exploration Incentive Scheme ("EIS") to conduct a two-hole diamond drill program to further evaluate mineralisation potential at Aries.

Core processing,logging and assaying is in progress.

Altan Rio acknowledges the support of the Western Australian Government for the Aries Diamond Drill Program

Altan Rio Chief Executive Officer Paul Stephen said:

This diamond drilling program is a significant step towards unlocking the deeper gold potential at Southern Cross. The drillholes will not only provide invaluable geological and structural information from drill core but will provide a platform for a Down Hole Electro Magnetic (DHEM) Survey with the potential to replicate the success of DHEM at our Pilot Gold project only a few kilometres to the north of this prospect.

Qualified Person

Mr. Neal Leggo,Principal Geologist,CSA Global Pty Ltd,is the independent Qualified Person as defined by National Instrument 43-101 who is responsible for the preparation of,and who has reviewed and approved,the scientific and technical disclosures in this news release.

Altan Rio Mining Limited (Altan Rio) is a West Australian-focused gold exploration company primarily focused on the Southern Cross Greenstone Belt,a prolific gold producing region responsible for well in excess of 12 million ounces.

To read the full announcement visit: www.altanrio.com/news/

Or contact:

Paul Stephen

Chief Executive Officer

Email: ps@altanrio.com

Neither the TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this release.