White gold was originally developed to imitate platinum, and is usually an alloy containing 25% nickel and zinc. If stamped 18 karat, it would be 75% pure gold.
White gold is an alloy of gold and at least one white metal, usually nickel or palladium. Like yellow gold, white gold is measured in karats.
White gold's properties vary depending on the metals and proportions used. As a result, white gold alloys can be used for different purposes; while a nickel alloy is hard and strong, and therefore good for rings and pins, gold-palladium alloys are soft, pliable and good for white gold gemstone settings. The highest quality white gold is usually at least 17 karat, and made up of gold and palladium, sometimes with trace levels of platinum for weight and durability, although this often requires specialized goldsmiths.
White Gold is an alloy of gold and silver or palladium. Nickel used to be used instead of silver or palladium, but nickel can cause skin reactions with some people. All high quality white gold does not use nickel for this reason. As white gold is a light gray color, it is sometimes plated with rhodium to give it more of a white coloring.
While some higher-quality white gold alloys retain their shine and lustre, most will be coated with a very thin layer of rhodium. This gives the naturally more-dull white gold a shine comparable to platinum or silver; however the rhodium may wear off over time.
Actually, they are true carat golds, just like yellow or red carat gold jewellery. They are gold alloys that look white rather than yellow. The white colour is achieved by careful choice of the alloying metals, which bleach the deep yellow of pure gold.
It is interesting to note that white golds for jewellery were originally developed in the 1920's as a substitute for platinum. Nowadays, they are a jewellery metal in their own right and currently very fashionable and desirable, particularly among the younger age groups. White golds are available up to 21 carat. They are often used to enhance diamonds and other gemstones. White gold bridal jewellery is increasingly popular.
Making gold white
Making gold white is similar to mixing colours in paints. Adding a red metal (copper) will tend to make gold red and adding a white metal tends to make gold paler and eventually white. Thus, all other alloying metals to gold, apart from copper, will tend to whiten the colour and so it is possible to make carat golds that are a reasonable white colour.
Whilst additions of any white metal to gold will tend to bleach it's colour, in practice, nickel and palladium (and platinum) are strong 'bleachers ' of gold, silver and zinc are moderate bleachers and all others are moderate to weak in effect.
This has given rise, historically, to 2 basic classes of white golds - the Nickel whites and the Palladium whites. The nickel-whites tend to have a colder white colour, whereas the palladium whites have a warmer colour. Good nickel whites tend to be hard and difficult to process. Good palladium whites tend to be soft, easy to process (but lost wax casting is more difficult) but are much more expensive, because of the price of palladium. Consequently, many commercial white alloys are thrifted in nickel or palladium and contain some copper; hence, colour is compromised. At the 8-10 carat (33.3 - 41.6% gold) level, gold-silver alloys are quite white, ductile although soft and are used for jewellery purposes.
White gold's properties vary depending on the metals and proportions used. As a result, white gold alloys can be used for different purposes; while a nickel alloy is hard and strong, and therefore good for rings and pins, gold-palladium alloys are soft, pliable and good for white gold gemstone settings. The highest quality white gold is usually at least 17 karat, and made up of gold and palladium, sometimes with trace levels of platinum for weight and durability, although this often requires specialized goldsmiths.
White Gold is an alloy of gold and silver or palladium. Nickel used to be used instead of silver or palladium, but nickel can cause skin reactions with some people. All high quality white gold does not use nickel for this reason. As white gold is a light gray color, it is sometimes plated with rhodium to give it more of a white coloring.
While some higher-quality white gold alloys retain their shine and lustre, most will be coated with a very thin layer of rhodium. This gives the naturally more-dull white gold a shine comparable to platinum or silver; however the rhodium may wear off over time.
Actually, they are true carat golds, just like yellow or red carat gold jewellery. They are gold alloys that look white rather than yellow. The white colour is achieved by careful choice of the alloying metals, which bleach the deep yellow of pure gold.
It is interesting to note that white golds for jewellery were originally developed in the 1920's as a substitute for platinum. Nowadays, they are a jewellery metal in their own right and currently very fashionable and desirable, particularly among the younger age groups. White golds are available up to 21 carat. They are often used to enhance diamonds and other gemstones. White gold bridal jewellery is increasingly popular.
Making gold white
Making gold white is similar to mixing colours in paints. Adding a red metal (copper) will tend to make gold red and adding a white metal tends to make gold paler and eventually white. Thus, all other alloying metals to gold, apart from copper, will tend to whiten the colour and so it is possible to make carat golds that are a reasonable white colour.
Whilst additions of any white metal to gold will tend to bleach it's colour, in practice, nickel and palladium (and platinum) are strong 'bleachers ' of gold, silver and zinc are moderate bleachers and all others are moderate to weak in effect.
This has given rise, historically, to 2 basic classes of white golds - the Nickel whites and the Palladium whites. The nickel-whites tend to have a colder white colour, whereas the palladium whites have a warmer colour. Good nickel whites tend to be hard and difficult to process. Good palladium whites tend to be soft, easy to process (but lost wax casting is more difficult) but are much more expensive, because of the price of palladium. Consequently, many commercial white alloys are thrifted in nickel or palladium and contain some copper; hence, colour is compromised. At the 8-10 carat (33.3 - 41.6% gold) level, gold-silver alloys are quite white, ductile although soft and are used for jewellery purposes.
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