Honolulu-Big Horn Mine (Gilbralter)

Listed as the Thorndike Mine on TopoZone.

From the California Journal of Mines and Geology, Vol. 47, No. 1, Jan. 1957:

4 claims are owned by John Thorndyke, Trona, California.

The deposit was discovered in 1907 and 25 cars of ore were shipped during the early operations. A part of this ore assayed 30 percent lead and 20 ounces of silver per ton. Southwest Lead and Zinc Company, M.H. Evans, president, Los Angeles, operated the property from 1942 through 1944 and shipped approximately 1300 tons of ore containing 550,000 pounds of zinc, 350,000 pounds of lead and 5,000 ounces of silver. Ore was trucked to Trona and shipped to various smelters.

The ore consists of replacement bodies in limestone and dolomitic marble. Four principle veins have been worked.

Honolulu claim has a 400-foot adit which follows a poorly defined zone of zinc sulphide ore, ranging in width from a thin seam to three feet and assaying 50 percent zinc and 10 to 15 percent lead. Some of the ore was stoped from above the adit level and in one place, a 35-foot winze was sunk on rich ore.

Carbonate adit is 135 feet above the parallel Honolulu adit. The vein which it follows strikes northward, dips eastward, and ranges from 2 to 10 feet in width. The ore was principally zinc carbonate with some lead carbonate. Some offshoots from the main zone enlarged into pockets or "rooms" of residual lead carbonate. A hanging wall fault contains ore, and in many places zinc carbonate is disseminated through what appears to be barren limestone. Ore from these workings was handled through a raise driven from the Honolulu adit below.

Iron vein adit, 130 feet west and 50 feet vertically below the Honolulu adit, follows an irregular but well defined vein, 2 to 5 feet wide, for a distance of 100 feet. A conspicuous gossan marks the surface outcrop of the vein which can be traced for several hundred feet. Vein matter consists of gossan containing small amounts of zinc and lead carbonate. A small pocket of rich lead carbonate ore was mined from this adit.

Big Horn workings, one-half mile east of Honolulu claim, consist of an 80-foot inclined shaft and several drifts. The Big Horn vein crops out boldly, strikes eastward and dips 20-30 degrees S.; it ranges from a few inches to 7 feet in width. Ore consists of cerussite and fine-grained galena, and many samples assay 50 to 70 percent lead. West of the shaft the ore is of good grade; east of the shaft it becomes increasingly poorer until it is finally truncated by a north-striking, east-dipping fault.

Before 1924, when a road was built to the mine, ore was hauled by pack-train. A 2150-foot aerial tram was installed later to deliver ore from the workings to the end of the road at the Honolulu camp.

The property is idle.