Goloid is an alloy

Alloy

An alloy is a mixture or metallic solid solution composed of two or more elements. Complete solid solution alloys give single solid phase microstructure, while partial solutions give two or more phases that may or may not be homogeneous in distribution, depending on thermal history...

 of silver

Silver

Silver is a metallic chemical element with the chemical symbol Ag and atomic number 47. A soft, white, lustrous transition metal, it has the highest electrical conductivity of any element and the highest thermal conductivity of any metal...

, gold

Gold

Gold is a chemical element with the symbol Au and an atomic number of 79. Gold is a dense, soft, shiny, malleable and ductile metal. Pure gold has a bright yellow color and luster traditionally considered attractive, which it maintains without oxidizing in air or water. Chemically, gold is a...

 and copper

Copper

Copper is a chemical element with the symbol Cu and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is soft and malleable; an exposed surface has a reddish-orange tarnish...

 patented by Dr. William Wheeler Hubbell on May 22, 1877 (U.S. patent #191,146). The patent specifies 1 part gold (about 3.6%), 24 parts silver (about 87.3%), and 2.5 parts copper (about 9.1%, all by weight); however, the patent also states that "The proportions may be slightly varied" and goes on to specify that the silver portion can range from 20 times to 30 times that of the gold, and the copper could range from one-eighth to one-twelfth (from 12.5% to 8.33%) of the total mixture. The patent specifies that the metals be separately melted, then mixed, along with "sulphate of sodium

Sodium sulfate

Sodium sulfate is the sodium salt of sulfuric acid. When anhydrous, it is a white crystalline solid of formula Na2SO4 known as the mineral thenardite; the decahydrate Na2SO4·10H2O has been known as Glauber's salt or, historically, sal mirabilis since the 17th century. Another solid is the...

 or sulphate of potassium

Potassium sulfate

Potassium sulfate is a non-flammable white crystalline salt which is soluble in water...

" in the amount of one part sulfate to one thousand parts metal. The alloy, in varying proportions (sometimes slightly out of these specifications), was used by the United States Mint

United States Mint

The United States Mint primarily produces circulating coinage for the United States to conduct its trade and commerce. The Mint was created by Congress with the Coinage Act of 1792, and placed within the Department of State...

 to strike pattern

Pattern coin

A pattern coin is a coin which has not been approved for release, produced for the purpose of evaluating a proposed coin design. They are often off-metal strikes, to proof standard or piedforts...

 dollars, sometimes called "metric dollars" (some were marked with "metric" in the coin design, while all had metal proportions and total coin weight as design features) from 1878 to 1880. Patterns of the same design were struck in other metals, including aluminum, copper, normal coin silver, lead

Lead

Lead is a main-group element in the carbon group with the symbol Pb and atomic number 82. Lead is a soft, malleable poor metal. It is also counted as one of the heavy metals. Metallic lead has a bluish-white color after being freshly cut, but it soon tarnishes to a dull grayish color when exposed...

, and white metal

White metal

The white metals are any of several light-colored alloys used as a base for plated silverware, ornaments or novelties, as well as any of several lead-base or tin-base alloys used for things like bearings, jewellery, miniature figures, fusible plugs, some medals and metal type.Some of the metals...

.

In the end, goloid was rejected as a coinage metal because it could not be distinguished from the normal U.S. 90% silver coin alloy without chemical analysis, thus inviting counterfeiters to use silver-copper alloys alone to make lower-value copies.