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For every day use, modern coinage is based on non-precious metals such as copper, nickel, zinc, iron and aluminium, with a preference being given to copper alloys.

Despite enthusiasm for progress, changes in the coinage field take place only very slowly, even if considerations of cost favour the use of cheaper materials.

Nickel is the most noble coinage material among non-precious metals. Its white, bluish tinged colour, its typical striking gloss and where resistance are unequalled by any other metal or alloy except previous metals.

The standard cupronickel alloy containing 75% Cu and 25% Ni is considerably cheaper than pure nickel, but he where and the corrosion resistance are still very acceptable. Cupronickel lends itself very well to striking is of light white colour and provides a good feel.

For both technical and economical reasons, cupronickel containing 84% Cu and 16% Ni has been used for some years. Its colour is rather yellowish-white. In some instances, variants with only 8 10% Ni are used and with this alloy the colour can be described as reddish-white.

3C Coinage material DIN Designation Main elements Density Kg / dm 3 Vickers Hardness Properties
Pure nickel Ni 99.2 Ni = 99.2% 8.9 85 White, magnetizable
Cupronickel 25 CuNi 25 Cu 75%, Ni 25% 8.9 80 White standard material
Cupronickel 16 CuNi 16 Cu 84%, Ni 16% 8.9 75 Yellowish-white
Cupronickel 10 CuNi 10 Cu 90%, Ni 10% 8.9 75 Reddish-white
Cupronickel 8 CuNi 8 Cu 92%, Ni 8% 8.9 70 Reddish

Alloys of copper, nickel and zinc are known as nickel silver or alpaca. With a copper content of between 60-80%, the colour changes from silver-white to goldenyellow as the nickel portion is reduced from 25 to 9%. Recently a composition with 6% Ni has been developed which can be hardly be regarded as nickel silver but rather as nickel-alloyed special brass.

3C Coinage material DIN Designation Main elements Density Kg / dm 3 Vickers Hardness Properties
Nickel silver 25 CuNi25Zn15 Cu 60%, Ni 25%,Zn 15% 8.8 85 White
Nickel silver 18 CuNi18Zn20 Cu 62%, Ni 18%,Zn 20% 8.7 85 White
Nickel silver 15 CuNi15Zn25 Cu 60%, Ni 15%,Zn 25% 8.7 85 Still white
Nickel silver 12 CuNi12Zn24 Cu 64%, Ni 12%,Zn 24% 8.7 85 Yellowish-White
Nickel silver 9 CuNi9Zn10 Cu 81%, Ni 9%,Zn 10% 8.75 70 Golden-yellow
Nickel silver 6 CuNi5.5Zn24.5 Cu 70%, Ni 5.5%,Zn 24.5 8.7 85 Light yellow

Binary copper alloys with zinc additions used for coining purpose containing 5-40% Zn. High-copper materials are usually designated as tombac, sometimes also as bronze which is, however, not correct. Alloy with higher zinc contents are called brass. A typical coinage material of this type is the so-called nickel brass which contains 20% Zn, 1% Ni, balance copper.
3C Coinage material DIN Designation Main elements Density Kg / dm 3 Vickers Hardness Properties
Tombac 95/5 CuZn5 Cu 95%, Zn 5% 8.9 70 Red
Tombac 90/10 CuZn10 Cu 90%, Zn 10% 8.8 70 Red
Tombac 85/15 CuZn15 Cu 85%, Zn 15% 8.8 70 Red-golden
Brass 72/28 CuZn28 Cu 72%, Zn 28% 8.6 75 Yellow
Brass 70/30 CuZn30 Cu 70%, Zn 30% 8.5 75 Yellow
Brass 64/36 CuZn36 Cu 64%, Zn 36% 8.4 85 Yellow
Brass 60/40 CuZn40 Cu 60%, Zn 40% 8.4 85 Yellow
Nickel-brass CuZn20Ni Cu 79%, Zn 20%,Ni 1% 8.7 70 Golden-yellow

Copper alloys with tin are known coinage bronze. Most of the alloys contain some zinc as well. In order to facilitate processing and also to reduce the metal costs, the tin content has been reduced the course of time and is now sometimes removed totally. The colour of coinage bronze is classified as copper-red.
3C Coinage material DIN Designation Main elements Density Kg / dm 3 Vickers Hardness Properties
Coinage bronze1 CuZn2.5Sn0.5 Cu 97%,Zn 2.5%,Sn 0.5% 8.83 80 Red
Coinage bronze2 CuZn3Sn2 Cu 95%,Zn 3%,Sn 2% 8.83 80 Red
Coinage bronze4 CuZn1Sn4 Cu 95%,Zn 1%,Sn 4% 8.83 80 Red

Coins with a sufficiently lasting golden- Coins with a sufficiently lasting goldenyellow colour have long been made from yellow colour have long been made from copper alloys containing 6-8% aluminium copper alloys containing 6-8% aluminium together with an addition of 2% nickel. together with an addition of 2% nickel. A special alloy with 6% nickel and 2% A special alloy with 6% nickel and 2% aluminium having a more reddish tint aluminium having a more reddish tint also comes within this group. According also comes within this group. According to field tests the best corrosion and tarnish to field tests the best corrosion and tarnish resistance is given by a copper alloys resistance is given by a copper alloys containing 5% nickel, 5% aluminium, containing 5% nickel, 5% aluminium, 1.2% iron and 0.8% manganese. This alloy 1.2% iron and 0.8% manganese. This alloy was developed in our laboratories and called was developed in our laboratories and called Monedor I. this material is characterized by Monedor I. this material is characterized by having a rho-density factor of 195-227 having a rho-density factor of 195-227W g/cm2, which offers a distinct advantage , which offers a distinct advantage over coinage materials when used in coin- over coinage materials when used in coinoperated automats.
3C Coinage material DIN Designation Main elements Density Kg / dm 3 Vickers Hardness Properties
Aluminium-bronze 8 CuA18 Cu 92%, A1 8% 7.7 90 Yellow
Aluminium-Nickel-Bronze 6 CuA1Ni2 Cu 92%, A1 6%,Ni 2% 8.1 85 Yellow
Aluminium-Nickel-Bronze 5 Cu51Ni2 Cu 93%, A1 5%,Ni 2% 8.1 85 Yellow
Aluminium-Nickel-Bronze F CuNi6A12 Cu 92%, Ni 6%,Al 2% 8.6 85 Reddish-brown
Monedor I CuNi5A15Fe Cu 88%, Ni 5%, Al 5%,Fe 1% 8.1 95 Golden-yellow Particularly tarnish-resistant;

Aluminium alloy having a specific density of only 2.7g/cm 3, are used as coinage material in exceptional cases only. Under normal circumstances, mainly low denominations are made of aluminium alloys containing 1-5% magnesium. These alloys are well suited for striking and, since the service-life of the coins is expected to be relatively short, their corrosion resistance is sufficient. They are mostly used for economical reasons.
3C Coinage material DIN Designation Main elements Density Kg / dm 3 Vickers Hardness Properties
Light alloy 1 A1Mg1 A1 99%, Mg 1% 2.69 85 White
Light alloy 2.5 A1Mg2.5 A1 97.5%, Mg 2.5% 2.68 85 White
Light alloy 3 A1Mg3 A1 97%, Mg 3% 2.66 85 White
Light alloy 3.5 A1Mg3.5 A1 96.5%, Mg 3.5% 2.66 95 White
Light alloy 4 A1Mg4 A1 96%, Mg 4% 2.65 95 White
Light alloy 5 A1Mg5 A1 95%, Mg 5% 2.64 95 White

Although unalloyed or unprotected iron has been used for coinage in emergencies, it does not belong to the coinage materials proper. With additions of at least 12.5 % chromium an alloy series called stainless irons is formed. Such a chromium iron (according to AISI 430) with 17-18% Cr, called Crofer 1700 M, is widely used. The alloy is ferritic and thus magnatizable. An addition of 8-9% nickel makes a stainless steel (to AISI 304) with is even more corrosion-resistant. 3C Cronifer 1809 is austenitic and is non-magnetic. Both the hardness and toughness of these steels complicate their strikability. As a rule, the coin relief must be reduced to one third of that of other materials.
3C Coinage material DIN Designation Main elements Density Kg / dm 3 Vickers Hardness Properties
Crofer 1300 X7Cr13 Fe 87%, Cr 13% 7.7 140 White, ferritic
Crofer 1700 X8Cr17 Fe 83%, Cr 17% 7.7 140 White, ferritic; AISI 430
Crofer 1809 X5CrNil89 Fe 73%, Cr 18%, Ni 9% 7.9 140 White, austentic; AISI 304 AISI 304

Coins made from iron with a metal cladding are in worldwide use. The colour can be varied according to the metal used for cladding from silvery-white top goldenyellow or copper-red. These products are magnetizable. The laminates produced by roll-bonding have a metal coating of at least 5% of the total thickness and usually 11% of the material combination. This ensures the coin relief is fully protected. Since the hardness of the product does not markedly differ from that of other customary coinage materials, the striking properties are excellent.
3C Coinage material DIN Designation Main elements Density Kg / dm 3 Vickers Hardness Properties
5% copper-clad steel on both side Cu=/Fe/=Cu a) Steel max 0.10% C b) Cu 7.95 90 Red,magnetizable;
5% brass-clad steel on both side CuZn=Fe/=CuZn a) Steel max 0.10% C b) Cu 75%, Zn 25% 7.95 90 Yellow, magnetizable
5% cupro-nickel-clad on both side CuNi=/Fe/=CuNi a) Steel max 0.10% C b) Cu 75%, Ni 25% 7.95 95 White, magnetizable
5% nickel-clad steel on both side Ni=/Fe/=Ni a) Steel max 0.10% C b) Ni 7.95 100 White, magnetizable

Initially the electro-plating of steel coins has been adopted only reluctantly. The process is now gaining increasing importance. Up to now gold-coloured deposits are still difficult.

Laminates of higher quality with combinations of non-ferrous metals are designed to make use of the physical properties of the various components with a view to coding the coinage materials used in automatic payment transactions. Besides laminate coding there are methods of combining at least two metals, for instance by means of ring-like arrangement or locally implanted rivets. However, these methods are confidential to specific end users and as such cannot be discussed at large.
3C Coinage material DIN Designation Main elements Density Kg / dm 3 Vickers Hardness Properties
Magnimat D CuNi=/Ni/=CuNi a) Ni
b)Cu 75%,
Ni 25%
8.9 85 White; high security in vending machines;
Magnimat F Ni=/CuNi/=Ni a) Cu 75%, Ni 25%
b) Ni
8.9 85 White; high security in vending machine;
Magnimat M CuNi9Zn10=/Ni/ =CuNi9Zn10 a) Ni
b) Cu 81%, Ni 9%, Zn10%
8.8 70 High security in vending machine;
Cupro Nickel clad Copper CuNi=/Cu/=CuNi a) Cu
b) Cu 75%, Ni 25%
8.9 75 White, red cutting edge;