High-Grade Gold Mineralization At Eureka Project

COEUR D'ALENE, ID - Timberline Resources Corporation reported assay results from the first seven reverse circulation (RC) drill holes of its 2020 drilling campaign at its 100%-controlled Eureka Gold Project in Nevada. These holes comprise 1,219m, or approximately 50% of the 2,400m RC program. This drilling falls within the existing Lookout Mountain resource footprint and had two objectives: (1) to confirm and extend high-grade (>3 g/t) gold mineralization in the vicinity of historic conventional rotary drill results; and (2) to infill the resource within and near the Lookout Mountain open pit. All of these drill holes intercepted significant disseminated gold mineralization.

Highlights: Hole BHSE-176 intercepted near surface high-grade gold mineralization, 15.24m averaging 10.09 g/t, beginning at 21.34m downhole depth. Within this interval, there are sub-intervals of 9.14m of 16.31 g/t, including 3.05m of 31.40 g/t; Holes BHSE-177 and 178 encountered shallow oxide gold within the existing resource, including 18.29m of 0.87 g/t (from surface), 48.77m of 1.00 g/t, and 59.44m of 0.63 g/t; and Holes BHSE-180, 181, and 182 confirmed northward and down dip extensions of mineralization beyond the historic Lookout Mountain pit, including gold intercepts up to 18.29m of 1.58 g/t in the latter of these holes.

Hole BHSE-176 was collared as a near offset to a historic hole that encountered multiple zones of high-grade gold in oxidized rocks less than 30m below surface. The historic high-grade gold zone was confirmed and extended by this hole, and host rocks are visibly oxidized and yielded high gold recoveries by cyanide leach analyses (averaging 94%).

President and CEO, Patrick Highsmith, said, "We are encouraged by these first results from the 2020 drill program because higher-quality samples from modern RC drilling have increased the grade and thickness of the high-grade mineralization in the Lookout Mountain resource area. These new data also improve the quality of our geological and assay information within the resource. Timberline's geological team has worked hard over the last year to re-log dozens of historic drill holes, and that work is clearly paying off allowing us to model and plan drill programs with maximum effect. Beyond these encouraging results, we eagerly await assays from deeper step-out holes in minimally-explored areas to the east of the resource."

Gold mineralization at Lookout Mountain is hosted by Cambrian sedimentary rocks including shale, limestone, and dolomite. Drill holes discussed in this news release focused on mineralization occurring in shale and interbedded limestone, the limestone often being altered to dolomite. Host rocks are variably and often intensely silicified, decalcified, sulfidized, argillized, and subsequently oxidized. Many shallow gold intercepts are hosted by oxidized jasperoid and chalcedonic silica, sometimes with high gold grades. Iron appears to be introduced along with hydrothermal dolomite, calcium carbonate having been leached out. Collectively these patterns of alteration are consistent with those observed in Carlin-Type Gold Deposits.

Oxidized rocks, or those in which the sulfide minerals (such as pyrite) have been oxidized, can yield higher gold recoveries during processing and better economics than sulfide mineralization.