Elizabeth

Site Name

Primary: Elizabeth

---

Commodity

Primary: Copper
Primary: Molybdenum
Secondary: Silver
Secondary: Lead
Secondary: Zinc
Secondary: Tin

---

Location

State: Alaska
District: Chistochina

---

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: Porphyry Mo, low-F

---

Orebody

Not available

---

Structure

Not available

---

Alterations

Alteration Type: L
Alteration Text: Argillic and sericite alteration; argillic alteration is probably accentuated by supergene acid solutions formed by oxidation of pyrite.

---

Rocks

Not available

---

Analytical Data

Not available

---

Materials

Ore: Ferrimolybdite
Ore: Chalcopyrite
Ore: Fluorite
Ore: Molybdenite
Ore: Pyrite
Gangue: Clay
Gangue: Quartz
Gangue: Sericite

---

Comments

Comment (Deposit): Model Name = Porphyry Mo (Cox and Singer, 1986; model 21b)

Comment (Geology): Age = Emplaced subseqent to or is related to the border phase of the Pennsylvanian to Permian, Ahtell pluton.

Comment (Exploration): Status = Inactive

Comment (Geology): Geologic Description = This low-grade, molybdenum porphyry occurs in a complex contact region of the Pennsylvanian to Permian, Ahtell pluton. A coarse-grained, porphyritic quartz monzonite phase of the Ahtell pluton appears to intrude the Border and Grubstake phases of the intrusion in the region south of Long Lake (Richter, 1966, fig. 2) the molybdenum deposit is mostly in the Border phase and in the overlying volcanic rocks of the Pennsylvanian to Permian, Slana Spur Formation.? the molybdenum deposit trends southeasterly from the ridge crest above Long Lake. On the ridge crest, it is about 400 feet wide; it extends over the ridge to the west for about 1,000 feet. To the southeast, the deposit widens to about 2,500-3,000 feet. The deposit is probably bounded by faults. On the surface the deposit is mainly rubble crop developed over a sericite-quartz-clay alteration zone with veinlets and disseminations of pyrite and minor molybdenite. Purple fluorite occurs locally. Quartz-molybdenum fragments mark the surface of the deposit and yellowish secondary ferrimolybdate occurs in surface materials (written communications, Emery Bailey Jr., ASARCO, 1969, and Kirk W. Stanley, 1970). The extent and shape of the deposit was defined by detailed geologic mapping and by a series of soil-sample lines running nearly east and west.? Because of poor exposures, the shape and size of much of the deposit was defined by a soil survey. Soils were analyzed for copper, molybdenum, lead, and zinc. Molybdenum was considered anomalous in excess of 20 ppm; Mo values are highest in a 1200-foot wide zone on the southeast side of the ridge. Copper and lead are partly coincident with molybdenum but also show strong anomalies on the lower southeast slope. Zinc is peripheral to molybdenum, copper, and lead. The highest zinc values are in Dry Creek (a local name for the creek in the center of section 30) that drains the southwest flank of the deposit. The distribution of zinc suggests that some may have been redistributed and concentrated in stream sediments. In absolute concentration, lead exceeds copper, zinc, and molybdenum. Lead in soils locally exceeds 0.1 percent. Apparently no samples were analyzed for gold.? Drilling in 1968 and 1969 shows that most of the deposit is very low grade, but two shallow holes drilled in 1968 found intercepts of rich mineralization. Both holes F and G cut ore grade material. Hole F, drilled northwest, assayed 0.519 % MoS2 over 26 feet; drill hole G, drilled northeastfrom the same location assayed 0.642 MoS2 over 41 feet. Both holes were drilled from the same location on the ridge between Dry and Moly Creeks at an elevation of about 4,500 feet (Moly Creek is a local name given to the creek in the southeast portion of section 13). None of the holes drilled in 1969 hit high grade mineralization. The maximum concentration of copper was about 0.3 percent; most samples ran 0.03 to 0.05 percent copper. Silver was not always assayed; its maximum concentration was 0.08 ounces per ton. The composite drill core was also analyzed spectrographically; tin was present in one sample at 50 ppm. Kirk Stanley later proposed two deeper holes nearer the top of the ridge where he believed better values would be found (written communication, 1970) A 2-foot-wide vein deposit that contains molybdenum reported by Richter (1966) is approximately on the northeast contact of the deposit.? the deposit is in part structurally controlled. Emery Bailey Jr., proposed that the deposit is bounded on east and southwest by post-Ahtell-pluton faults that control the courses of Moly and Dry Creeks (written communication, 1969). The deposit appears to be open to the southeast under upper Hidden Creek, but the best molybdenum zone appears to be near the top of the ridge in the northwest part of the deposit.

Comment (Deposit): Other Comments = Additional information can be obtained from Ahtna Minerals in Anchorage, Alaska.

Comment (Reference): Primary Reference = Richter, 1966

Comment (Workings): Workings / Exploration = The deposit was discovered in 1957 by Au Noc Ho and Kirk W. Stanley but no work was done until 1968 (Stanley, written communication, 1970). The site was visited and mapped at a reconnaissance scale by Richter (1966). Stanley's and Richter's geologic mapping and new discoveries led to renewed prospecting in the area. The molybdenum porphyry was initially covered by 95 federal claims, Elizabeth 20 to 115, owned jointly by the Ptarmigan Company and investors. The Ptarmigan Company, a company formed by Kirk Stanley to work on prospects near the Ahtell pluton, conducted a geochemical survey in 1968 and drilled six shallow AX holes. The claims were leased to ASARCO in 1969 who mapped the area in detail and drilled seven BX holes; the deepest hole, no. 6, was 400 feet in length. Drilling was fairly difficult; holes tended to swell shut. ASARCO did not find enough mineralization to warrant further work by them and little has been done since 1969.

---

References

Reference (Deposit): Richter, D.H., and Matson, N.A., Jr., 1972, Metallic mineral resources map of the Gulkana quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-419, 1 sheet, scale 1:250,000.

Reference (Deposit): MacKevett, E.M., Jr., and Holloway, C.D., 1977, Map showing metalliferous and selected non-metalliferous mineral deposits in the eastern part of southern Alaska: U.S. Geological Survey Open-File Report 77-169-A, 99 p., 1 sheet, scale 1:1,000,000.

Reference (Deposit): Richter, D.H., and Matson, N.A., 1968, Distribution of gold and some base metals in the Slana area, eastern Alaska Range, Alaska: U.S. Geological Survey Circular 593, 20 p.

Reference (Deposit): Cobb, E.H., 1979, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Gulkana quadrangle, Alaska: U.S. Geological Survey Open-File Report 79-1247, 36 p.

Reference (Deposit): Richter, D.H., 1966, Geology of the Slana district on south-central Alaska: Alaska Division of Geological and Geophysical Surveys Geological Report 2l, 36b p., 3 sheets, scale 1:63,360.

---

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.