The Irwin Property is located south of Currant in the Grant Range, Nye County. It is 150 km ENE of Tonopah and is accessible by 4x4 road from the Railroad Valley road. The property is in the Troy Mining District which has produced high grade gold and silver sporadically since the first discoveries were made in 1869. The Irwin Property covers several small underground workings and an abandoned mill in Irwin Canyon, staked in 1905 and developed in the early 1900’s. The southernmost vein, the No. 1 Vein, was opened in two shafts and a drift at the 80’ level. The No. 2 Vein, approximately 100 m to the WNW was developed with a 40’ shaft and a lower drift. Approximately 450 m to the NE at the Mayolli showings, two low angle inclines were driven along a mineralized contact with 100 ft of drifting at the bottom of one and 20 ft of drifting at the bottom of the other. Ore from several small nearby mines was milled at Irwin Camp Mill, in the canyon west of the underground workings. Milling was conducted as late as 1986 and the property was subsequently staked by individuals. Millsite, Placer and Lode claims were staked and held in the property area through the early 1990’s and from 2008 through 2014. Notable claim holders during the latter period include Silver Viking Corp. (Einar Erickson), Amador Capital LLC, and William Sherriff.
The Irwin Property hosts intrusion-related mesothermal quartz vein style gold mineralization. Precambrian metasediments and carbonates are intruded by Oligocene granodiorite.
Historical workings are found at three showings. The No. 1 Vein in the southern portion of the property can be traced along a slot trench, an adit and in shafts over a strike length of 40 m. The No. 2 Vein, approximately 100 m to the WNW, has a strike length defined by workings of approximately 70 m. Both veins strike approximately 750 and appear to be steeply dipping. At the Mayoli showing, approximately 450 m NE of the No. 1 Vein, mineralization along a fault contact between granodiorite and limestone was explored in two adits approximately 20 m apart.
Quade (1986) (NBMG Document 49000012) has described the mineralization at the No. 1 and No. 2 Veins as consisting of quartz veins, irregular small pods of sheared and crushed country rock, and stringers. Gold is also contained in marginal gouge layers up to 5 cm wide. A 1986 NBMG sample (# 3108) in the area of the No. 2 Vein returned 7.5 g/t Au from a sample analyzed by atomic absorption. At the Mayolli showing, a 1986 NBMG sample of dump material returned 3.8 ppm Au. Mineralized dump samples and a sample from the back of the No. 1 Vein collected by Silver Range consist of brown-orange weathering ribbon quartz veins. The quartz is glassy to grey, 2 to 5 mm, intergrown and banded and occurs together with abundant limonite. Mineralized samples contain 8-15% pyrite and trace to 8% galena, both disseminated and in clots. Initial sampling by Silver Range in 2019 returned 2.22 g/t Au and 96 g/t Ag from a 40 cm chip sample across the back of the exposed No. 1 Vein and 2.72 g/t Au from a grab sample of dump material from the No. 2 Vein.
Silver Range plans to conduct geophysical and soil geochemical surveys at Irwin to map the extent of the known mineralization and to define drill targets.