Hoadley

Site Name

Primary: Hoadley
Secondary: Hoadley Brothers

---

Commodity

Primary: Gold
Secondary: Bismuth

---

Location

State: Alaska
District: Ketchikan

---

Land Status

Not available

---

Holdings

Not available

---

Workings

Not available

---

Ownership

Not available

---

Production

Not available

---

Deposit

Record Type: Site
Operation Category: Prospect
Operation Type: Unknown
Years of Production:
Organization:
Significant:

---

Physiography

Not available

---

Mineral Deposit Model

Model Name: Low-sulfide Au-quartz vein
Model Name: Polymetallic veins

---

Orebody

Not available

---

Structure

Not available

---

Alterations

Alteration Type: L
Alteration Text: Greenschist-grade metasedimentary country rocks are contact metamorphosed to hornblende hornfels near contacts of Tertiary intrusive rocks.

---

Rocks

Not available

---

Analytical Data

Not available

---

Materials

Ore: Arsenopyrite
Ore: Gold
Ore: Pyrite
Ore: Pyrrhotite
Ore: Tetradymite
Gangue: Quartz

---

Comments

Comment (Deposit): Model Name = Polymetallic veins or low-sulfide, Au-quartz veins (Cox and Singer, 1986; models 22c or 36a)

Comment (Deposit): Other Comments = the property has been covered by housing construction in the city of Ketchikan. In some early reports, the prospect was also referred to as Hoadley Brothers (Cobb and Elliott, 1980, p. 56).

Comment (Workings): Workings / Exploration = The Hoadley prospect was discovered around 1900 and developed by opencuts, adits, and a 27-foot shaft. Other early developments included an arrastre and a Gibson mill. In 1995, the old workings were covered by a condominium. A 1.5-foot-wide sample across vein rubble contained 88.25 ppm Au (Maas and others, 1995).

Comment (Geology): Age = Cretaceous or younger.

Comment (Reference): Primary Reference = Wright and Wright, 1908; Maas and others, 1995

Comment (Geology): Geologic Description = This part of Revillagigedo Island is underlain mainly by marine, pelitic sedimentary rocks and subordinate andesitic or basaltic volcanic rocks that are intruded by Cretaceous stocks, sills, and dikes of feldspar-porphyritic granodiorite, and by a stock and probably related plugs of Tertiary gabbro (Berg and others, 1988). The strata were regionally metamorphosed to greenschist-grade phyllite and semischist in Late Cretaceous time. They subsequently were contact metamorphosed to hornblende hornfels: locally, near some of the Cretaceous granodiorite contacts, and, more widely, peripheral to the Tertiary gabbro. The premetamorphic age range of the strata is uncertain. Berg and others (1988) note that they closely resemble Upper Jurassic to mid-Cretaceous flysch and volcanic rocks nearby on Gravina Island. The country rocks are cut by a high-angle fault along Tongass Narrows that displays about 4 miles of right-lateral offset.? the Hoadley deposit consists of sulfide-bearing quartz veins and argillaceous schists that strike northwest and are intruded by sills or dikes ranging in composition from syenite to gabbro (Wright and Wright, 1980, p. 151-152). The veins are mainly in the intrusive rocks, vary from 4-24 inches thick, and are up to a few hundred feet long. An older set of veins contains chiefly pyrite and pyrrhotite and strikes N and dips W. A younger set of thinner veins, characterized by arsenopyrite, free gold, and minor tetradymite, strikes NW and dips SW. According to Maas and others (1995, loc. 270: p. 194-200), the deposit, which in 1995 was covered by a condominium, is at a syenite-slate contact and consists of a quartz vein containing bands and disseminations of pyrite and arsenopyrite. A 1.5-foot-wide sample across vein rubble contained 88.25 ppm Au (Maas and others, 1995). ? the Hoadley prospect was discovered around 1900 and developed in the early 1900s by opencuts, adits, and a 27-foot shaft. Other developments included an arrastre and a Gibson mill. A small amount of gold probably was recovered at that time, but there is no public record of any such production.

Comment (Production): Production Notes = A small amount of gold probably was recovered in the early 1900s, but there is no public record of any such production.

---

References

Reference (Deposit): Cobb, E.H., and Elliott, R.L., 1980, Summaries of data on and lists of references to metallic and selected nonmetallic mineral deposits in the Ketchikan and Prince Rupert quadrangles, Alaska: U.S. Geological Survey Open-File Report 80-1053, 154 p.

Reference (Deposit): Berg, H.C., Elliott, R.L., and Koch, R.D., 1988, Geologic map of the Ketchikan and Prince Rupert quadrangles, southeastern Alaska: U.S. Geological Survey Mineral Investigations Series Map MF-1807,27 p., scale 1:250,000.

Reference (Deposit): Maas, K.M., Bittenbender, P E., and Still, J.C., 1995, Mineral investigations in the Ketchikan mining district, southeastern Alaska: U.S. Bureau of Mines Open-File Report 11-95, 606 p.

Reference (Deposit): Wright, F.E., and Wright, C.W., 1908, The Ketchikan and Wrangell mining districts, Alaska: U.S. Geological Survey Bulletin 347, 210 p.

Reference (Deposit): U.S. Bureau of Mines, 1977, Claim map, Ketchikan quadrangle: U.S. Bureau of Mines Map 120, scale 1:250,000.

Reference (Deposit): Elliott, R.L., Berg, H.C., and Karl, Susan, 1978, map and table describing metalliferous and selected nonmetalliferous mineral deposits, Ketchikan and Prince Rupert quadrangles, Alaska: U.S. Geological Survey Open-file Report, 78-73-B,17 p., scale 1:250,000.

---

The Top Ten Gold Producing States

These ten states contributed the most to the gold production that built the West from 1848 through the 1930s. The Top Ten Gold Producing States.