Instruction
1
Gold coins in cleaning almost do not need, because the rust of them not striking. If the coin is dirty, just wash them in warm soapy water and dry by placing between two pieces of soft tissue. Avoid friction. Even the soft fabric when cleaning out rust and dirt can damage the finish of the coin. Or rather, the coating is protected from the dust.
2
With silver coins harder. It all depends on the degree of oxidation of the metal sample. High-grade silver, long lying in the ground, covered by a dense and firm oxide layer. To get rid of the oxides can putting the coin in ammonia (10% ammonia 90% water). There is no ammonia? Put "patient" in a solution of baking soda (30%). After a few hours of simmering in another solution, the coin will be released from the oxide layer. To speed up the process by heating the solution to boiling and periodic cleaning of the oxidized areas with a soft toothbrush.
3
If high-grade silver coin small plaque oxides, clean the paste of toothpaste, baking soda and ammonia. Mix the slurry until no lumps.
4
The base alloys of silver turn green when they oxidize. They can be cleaned with a 10% solution of Trilon B. getting Rid of the green, treat the coin gruel, which was mentioned above.
5
On copper coins over time, there is patina which can be brown, green, black colors and their shades. If the layer of smooth patina and traces of corrosion are seen, patina cleaning is not necessary. On the contrary, it will prevent the coin from harmful external influences.
6
Oxidized copper coin clear slowly active reagents such as Trilon B. the thicker the oxide layer, the longer the reagent is a coin you need to survive.
7
Bronze coins go the same way as with copper. However you need to remember that ammonia and Trilon changing the color of bronze. It can darken to brown or even black. The Shine of coins you can restore it by washing it in warm water with toothpaste.