Ruby and Golconda Prospect, Nome Mining District, Nome Census Area, Alaska, USAi

Regional Level Types
Ruby and Golconda Prospect	Prospect
Nome Mining District	Mining District
Nome Census Area	Census Area
Alaska	State
USA	Country

Sometimes confused with the nearby Lilly prospect (NM189).
Location: This prospect is at an elevation of about 900 feet on the divide between the headwaters of Twin Mountains Creek and Butterfield Canyon. The prospect is about one-quarter mile northwest of the Lilly prospect (NM189). The location is near the center of section 28, T. 9 S., R. 34 W., Kateel River Meridian.
Geology: Mertie (1918 [B 622-I, p. 442]) reported azurite and malachite in fractured quartz on the Ruby and Golconda claims at the head of Twin Mountains Creek. A copper-bearing quartz vein located by Kennecott Exploration Company at the head of Twin Mountain Creek in 1993 is assumed to be the vein described by Mertie. Hummel (1962 [MF 247, locality 9]) reported copper at the nearby Lilly prospect (NM189) but he may have confused the Lilly and Ruby and Golconda prospects because the Lilly deposit apparently does not contain copper (C.C. Hawley, unpub. data, 1993). The Ruby and Golconda deposit is a concordant quartz vein about 2 feet thick. The vein is coated with limonite and contains less than 2 percent malachite and azurite as fracture coatings and about 1 percent disseminated chalcopyrite in grains less than 0.2 inch across. The quartz strongly resembles limonite-stained sugary quartz boulders found throughout the western part of the Nome district, most commonly in stream float. Such boulders contain sparsely disseminated chalcopyrite and few other sulfide minerals. The concordant nature of the quartz vein at Ruby and Golconda and similar occurrences elsewhere suggests that these copper-bearing quartz veins are very early, having formed essentially by metamorphic processes prior to the main gold-mineralizing events at Nome. This early quartz could correlate with the weakly metallized quartz rods at the upper Butterfield Creek deposit (NM164).
Workings: A short tunnel was reported but was not found by Mertie (1918) or by C.C. Hawley in 1993.
Age: Pre-Late Cretaceous; possibly as old as early Paleozoic, the protolith age of the enclosing metamorphic rocks.
Alteration: Oxidation.

Commodities (Major) - Cu
Development Status: None
Deposit Model: Concordant copper-bearing quartz vein in schist.

Other Databases

Link to USGS - Alaska:	NM188

Other Regions, Features and Areas containing this locality

References