Tombac - Common Types

Common Types

• Modern CuZn15

(DIN: CuZn15 ; UNS: C23000 ; BS: CW 502L (CZ 102) ; ISO: CuZn15) Tombak with a gold colour, very good for cold forming, suitable for pressing, hammering, embossing.

• modern CuZn12

(not standardized) Same characteristics and applications as CuZn15; slightly different colour.

• modern CuZn10

(DIN: CuZn10 ; UNS: C22000 ; BS: CW 501L (CZ 101) ; ISO: CuZn10) Similar characteristics and applications as CuZn15 und CuZn12; noticeable reddish colour.

• modern White Tombak

CuZn10- that is Zinc content 10%, with trace arsenic

• modern Enamel Tombak or Emailler Tombak

An alloy of 95% copper and 5% zinc is very suitable for enamelling, therefore the name.
Ure notes the following forms of Tombak in widespread use during the time the text was published (1856):

• • "Gilting Tombak":
    • Copper 82%, Zinc 18%, Lead 1.5%, Tin 3%
    • Copper 82%, Zinc 18%, Lead 3%, Tin 1%
    • Copper 82%, Zinc 18%, Lead, Tin 0.2%

• • "French Tombak for sword handles", pommels and fittings:

Copper 80%, Zinc 17%, 3% Tin

• • "Yellow Tombak of Paris" for gilt ornaments:

Copper 85%, Zinc 15%, trace% Tin

• • "Hanover Tombak":

Copper 85.3%, Zinc 14.7%

• • Chrysochalk

Copper 86%, Zinc 14%

• • "Red Tombak of Paris"

Copper 90%, Zinc 7.9%, 1.5% Lead

• • "Red Tombak of Vienna"

Copper 97.8%, Zinc 2.2%
Piggot states the brass used for machinery and locomotives in England was composed of Copper 74.5%, Zinc 25%and Lead 0.5%- which would make it a tombak according to Ure. Piggot's own definition of tombak is problematic at best: "red brass or tombak as it is called by some, has a great preponderance of copper, from 5 ounces of zinc down to 1/2 ounce of zinc to the pound "