Why should jewellery be plated?
There are many reasons why jewellery should be plated.
Metals such as copper, brass and other base metal darken or turn green over time, especially if you wear the piece regularly. If you plate your jewellery in a precious metal then your jewellery can retain its look with minimal tarnishing.
Corrosion and Rust Resistance
Metals such as brass corrode quickly, particularly if in contact with the salt in sweat.
Plating will prevent rust and corrosion, protecting from environmental conditions and human produced chemicals.
Gold is hypoallergenic, protecting those with allergens to other base metals.
Jewellery makers and artists choose to craft with brass, bronze, silver or copper as it is easier to work with and more affordable. Once these metals are plated in a thin layer of gold plating, the value of the jewellery greatly increases. The cost to plate is distinctly cheaper than the increase in value following plating.
How to find out if your gold jewellery is plated?
Solid gold jewellery is made of a gold alloy which is consistent throughout the item.
Gold plated jewellery is a non-gold metal that is coated with a thin film of gold giving it a gold appearance, making it hard to tell between the two. Sterling Electro Plating only plates with 23.5C gold. The other 0.5 is cobalt, which makes it hard and longer wearing.
To establish the composition, check its stamps.
No mark does not necessarily mean solid gold, it may be plated but simply not stamped.
It is also important to note that solid gold still consists of an alloy of gold and other metals. The carat stamp indicates the purity of this mixture dependent on how much gold it contains
If the stamp does not give you a guide there are a few other methods that you can employ.
|RGP||Rolled Gold Plate|
|HGP||Heavy Gold Plate|
|HGE||Heavy Gold Electroplate|
|Gold Purity Stamps|
|375||9 Carat Gold 37.5% Purity|
|585||14 Carat Gold 58.5% Purity|
|750||18 Carat Gold 75% Purity|
|916||22 Carat Gold 91.6% Purity|
|990||24 Carat Gold 99% Purity|
|999||24 Carat Gold 99.9% Purity|
This is best conducted by a jeweller, who can expertly monitor a colour change when acid is applied to a sample of the piece. The colour change should reflect the metal composition.
If you’re buying a piece of jewellery, the price of jewellery is often a key indicator as to the quality of the metal. If you are being sold 24 Carat, then look for the mark and see if the price matches. If not, then the chances are it is a fake. Plated pieces enable affordability giving the look of gold without the price tag.
XRF Testing / Magnetic Testing
Sterling Electro Plating is one of the few Electroplaters to have a X-Ray Fluorescence Machine, so we can determine base metals (alloy) or coating thickness, allowing us to give best advice on process. Magnetic testing is inconclusive, gold is not magnetic however the alloy within the gold might be, or if it is gold plated over a non-metallic metal then this would also not be magnetic.