Sunday, November 20, 2011
White Gold
10:06 AM | 
Posted by
bayan |
| All our white gold jewellery is compliant with Nickel free directives, with less than 0.05% nickel content, with release rates less than 0.5 micrograms per square centimetre per week, as determed in EN1811:1998 and EN1810:1998. We use an expensive silver-rich alloy to produce the white colour which is best described as a warm white. This whiteness is then enhanced with a rhodium plating and whilst this will fade in time, it can easily be reapplied to restore the original finish by a working jeweller. Gold is yellow, copper is reddish, and all other metals are a silvery grey in colour.  There are however gold alloys, that is mixes of differing metals, that appear grey/white.White gold (alloy) became popular around 1920 as a substitute for platinum, as platinum was quite expensive. Simply mixing a white and yellow metal together will not produce a colour in the same way that mixing paint does. The most common metal used to 'bleach' gold is nickel which is both inexpensive and provides a good platinum look-alike in 18ct alloys. It has however been linked to dermatitis through allergic reactions with the skin. It has also been suggested that it may be slightly carcinogenic. A recent E.U directive has indicated that soon all jewellry will have to be nickel safe with only a few ppm being allowable. |
A typical white gold alloy might be
| Carat and Colour | Pure 24ct | Silver | Copper | Zinc | Nickel | Palladium |
| 18ct White gold | 75% | NIL | 5.5% | 5% | 14.5% | NIL |
| Nickel Free | ||||||
| 18ct White gold | 75% | 4% | NIL | NIL | NIL | 17% |
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