** IRIS Metals shares IR1.AX up 5% to A$0.105
** Earlier, it rose as much as 10% to A$0.110, biggest intraday pct gain since June 25
** Lithium explorer expands Tin Mountain Project in Black Hills, South Dakota with acquisition of 752-hectare Tin Mountain Extension Property
** Acquired land includes 93 federal mining claims; paid via issuance of $550,000 in co's shares, $300,000 cash, and royalties
**YTD, IR1 down 55.3%
(Reporting by Nichiket Sunil in Bengaluru)
((Nichiket.Sunil@thomsonreuters.com))