Thickness Strip. Coinage strip metal, rolled to the proper gauge or thickness waiting to be blanked. A different thickness strip is required for each denomination of coin as each may be a different thickness. Thickness strip must be made from an ingot of correct composition before being processed in a rolling mill, where it is rolled to a precise diameter to meet the specifications of a particular coin, a prescribed thickness.

The United State Mint, prior to 1964, rolled and blanked all thickness strip at the Mint for all coins. Since the introduction of clad composition in 1964, the United States Mint receives clad strip in rolls from outside suppliers. These are blanked within the mint (with the exception of cent blanks which are blanked by the supplier). The thickness strip for both pre 1964 coins and current clad strip is as follows:

United States Coins

Denomination

Face Value

Diameter

Thickness

Standard (gross) weight

Weight tolerance

Fineness

Fineness tolerance

Pure gold or silver content

Minimum legal weight of new coin

Abrasion Tolerance

Inches

Millimeters

Inches

Millimeters

Troy Ounces

Grains

Grains

Thousandths

Thousandths

Grains

Grains

0.5% for 20-years wear. Grains

Minimum current weight after 20 years wear. Grains.

Annual abrasion within legal limit. Grains

Actual coefficient of annual abrasion (from experiments). Grains

Gold

Double Eagle

$20

1.350

0.0968

1.07500

516.0

0.50

900

1

464.4

515.50

2.58

513.42

0.1290

0.0860

Eagle

$10

1.060

0.08

0.05375

258.0

0.50

900

1

232.2

257.50

1.29

256.71

0.0645

0.0430

Half Eagle

$5

0.848

0.0582

[Indian]

0.26875

129.0

0.25

900

1

116.1

128.75

0.645

128.355

0.0322

0.0215

Quarter Eagle

$2.50

0.700

0.042

0.134375

64.5

0.25

900

1

58.05

64.25

0.322

64.178

0.0161

0.0107

Dollar

$1.00

0.585

0.033

0.053575

25.8

0.25

900

1

23.22

Silver

Dollar

$1.00

1.500

38.100

0.114

2.8956

0.899375

412.50

60.00

900

6

371.25

411.00

Half Dollar

$0.50

1.205

30.607

0.086

2.1844

0.400875

192.90

4.00

900

6

173.61

101.40

Quarter Dollar

$0.25

0.955

24.257

0.067

1.7018

0.200937

96.45

3.00

900

6

86.805

94.95

Dime

$0.10

0.705

17.907

0.053

1.3462

0.080735

38.58

1.50

900

6

34.722

37.08

Minor

Five Cent

$0.05

0.835

21.209

0.078

1.9812

0.16075

77.16

3

Five cent, silver

$0.05

0.835

21.209

0.078

1.9812

0.16075

77.16

3

One Cent, bronze

$0.01

0.750

19.050

0.062

1.5748

48

2

95 Cu, 5 Zn + Sn

One cent, copper-zinc (1942, 1944-47)

$0.01

0.750

19.050

0.062

1.5748

0.1

48

2

95 Cu, 5 Zn

One cent, zinc coated steel (1943)

$0.01

0.750

19.050

0.062

1.5748

0.08646

41.5

3

steel with.001-in zinc plating

One Cent, zinc coated steel (1943)

$0.01

0.750

19.050

0.062

1.5748

0.08854

42.5

3.5

steel with.001-in zinc plating

A standard silver dollar contains 0.7734375 troy ounces of pure silver.

All standard silver subsidiary coins contain 0.723375 troy ounces of pure silver per one-dollar face value.

One cent coins of copper/zinc composition contained a trace of tin sufficient to be detected on analysis.

Source: "Regulations for the Transaction of Business at the Mints, Assay Offices, and Bullion Depositories of the United States," Treasury Department, U.S. Mint. December 1, 1947.

$ Liberty = 0.065 thick

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