GRADE AND TONNAGE MODEL OF POLYMETALLIC REPLACEMENT DEPOSITS

By Dan L. Mosier, Hal T. Morris, and Donald A. Singer

COMMENTS Carbonate-hosted replacement and transitional vein and other replacement deposits are included. Only districts with combined production and reserves of at least 100,000 tonnes are used. Tonnages for many districts, particularly in the U.S. are biased because only production data were available. The break in slope in the zinc grade plot at about 1 percent may be related to early difficulties of processing zinc oxides, and the consequent underreporting of zinc grades where estimates were based on production. Lead grade is correlated with silver (r = 0.55, n = 45). See figs. 69-74.

Figure 69. Tonnages of polymetallic replacement deposits.

Figure 70. Lead grades of polymetallic replacement deposits.

Figure 71. Zinc grades of polymetallic replacement deposits.

Figure 72. Copper grades of polymetallic replacement deposits.

Figure 73. Silver grades of polymetallic replacement deposits.

Figure 74. Gold grades of polymetallic replacement deposits.

DEPOSITS

Name Country

American Fork USUT

Atacocha PERU

Bell USNV

Big Cottonwood-L.C. USUT

Blue Bell CNBC

Bolkardag TRKY

Bristol (Jack Rabbit) USNV

Cerro Gordo USCA

Chalchihuites MXCO

Charcas MXCO

Cortez USNV

Darwin USCA

Drina YUGO

East Tintic USUT

El Porvenir (Milpo) PERU

Eureka USNV

Hunnan CINA

La Encantada MXCO

La Reforma MXCO

Lampazos MXCO

Laurium GREC

Liaoning CINA

Lone Mountain USNV

Magdalena USNM

Maria Christina CILE

Mazapil MXCO

Nakatatsu JAPN

Mitate JAPN

Naica MXCO

New Calumet CNQU

Olympias Chalkidiki GREC

Ophir USUT

Park City USUT

Plomosas MXCO

Rush Valley USUT

San Francisco USUT

Santa Eulalia MXCO

Santander PERU

Sasa-Toranica YUGO

Silva-Aysen CILE

Sombrerete MXCO

Spruce Mountain USNV

Star USUT

Sumadisa YUGO

Tecopa USCA

Tintic USUT

Tombstone USAZ

Trepca-Kopaonik YUGO

Velardepa MXCO

White Pine USNV

Yellow Pine USNV

Zimapan MXCO