Snowflake Mine, Nome Mining District, Nome Census Area, Alaska, USAi

Regional Level Types
Snowflake Mine	Mine
Nome Mining District	Mining District
Nome Census Area	Census Area
Alaska	State
USA	Country

Location: The Snowflake placer mine is at Dexter, in the north headwaters of Dexter Creek (NM303). It is at an elevation of about 600 feet on the south side of the divide between Nekula Gulch and Deer Gulch. The map location is just inside the south-central boder of section 30, T. 10 S., R. 33 W., Kateel River Meridian. It is included in locality 117 (Dexter Hill) of Cobb (1972 [MF 463], 1978 [OFR 78-93]).
Geology: The Snowflake mine is one of several near the divide between upper Anvil Creek (NM236) and Dexter Creek (NM303) at surface elevations of about 450 to 600 feet, where high-level gravels were placer mined for gold. These deposits were in gravels that ranged from a few feet to 150 feet thick and commonly were very rich (Brooks and others, 1901). The richest pay was near bedrock and in decomposed or fractured bedrock. The high-level gravels were mined mostly by drifting, but some hydraulic mining also took place. The section exposed in the main shaft of the Snowflake mine included 5 feet of muck and gravel containing granite and gneiss boulders above 125 feet of silt and gravel on bedrock; the lower 3 to 9 feet of gravel was auriferous. West of the shaft, the pay streak was 100 feet wide on bedrock but to the east this paystreak was on older gravels. A winze sunk 70 feet east of the main shaft reached bedrock 100 feet deeper, where another pay streak was developed on bedrock (Collier and others, 1908). The pay at the Snowflake mine ran about 0.3 ounce of gold per cubic yard; the gold was bright and subangular to crystalline (small octahedrons were visible), and some nuggets included fragments of quartz and calcite. The largest nugget recovered by 1903 weighed more than 9 ounces (Collier and others, 1908). The high-level gravels were originally interpreted to be alluvial deposits in stream channels of former drainage systems, but more recent interpretations describe them as glacial outwash-related material (Cobb, 1973 [B 1374]; Nelson and Hopkins, 1972). The presence of erratic granite boulders and other exotic rock types suggests a glacial origin, but the exotic clasts are commonly in near-surface materials and not distributed throughout the high-level gravels (Moffit, 1913). The origin of the high-level gravels thus still seems in question. The richness of some of the placers suggests extensive reworking, proximity to lode sources, or both. The Anvil fault transects the area near Nekula Gulch. The Anvil fault is a through-going, high-angle structure that juxtaposes different types of graphitic schist in this area (Hummel, 1962 [MF 247]). Bedrock is mostly graphitic schist, probably of early Paleozoic protolith age (Hummel, 1962, [MF 247]; Sainsbury, Hummel, and Hudson, 1972 [OFR 72-326]; Till and Dumoulin, 1994; Bundtzen and others, 1994).
Workings: Workings at the Snowflake mine were underground. They included a 130-foot-deep main shaft, a winze sunk 70 feet east of the main shaft to the 230-foot level, and drifts trending N 60 W and S 60 E from the main shaft (Collier and others, 1908; Moffit, 1913).
Age: Quaternary.
Production: Production from the high-level gravels of the general area totaled about 100,000 ounces by 1903 (Collier and others, 1908). The pay ran about 0.3 ounce of gold per cubic yard at the Snowflake mine (Collier and others, 1908).

Commodities (Major) - Au
Development Status: Yes; small
Deposit Model: Alluvial placer Au (Cox and Singer, 1986; model 39a).

Other Databases

Link to USGS - Alaska:	NM241

Other Regions, Features and Areas containing this locality

References