Pardon me for disappearing for so long. Was erm... busy. =p
Anyhow, lemme cont with today's trivia.. i know u are dying to know more. hehehe.
The question of the day is: Is white gold really Gold?
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the answer to the above qn is... yes... and... no...
As some of you might already have known, there really is no such thing as white gold. The so-called white gold selling in those goldsmith shops in ur neighbourhood are actually alloys of gold. These alloys appear either grey, white or silver and are all known to the layman as White Gold.
A bit of info abt the color of gold:
The yellow colour of gold is caused by gold absorbing violet and blue light, but reflecting yellow and red light.
Because real pure gold is very soft, it is usual to mix it with other metals to produce an alloy. (for those who dunno, an alloy is simply a mixture of two or more metals)
I was quite surprised to find out that there are many ways of producing white gold. The most common ways to produce white gold is to mix gold with nickel, zinc, and palladium.
It is said that the above metals produce a whitening or bleaching effect and by simply mixing the two metals together, you produce a difference in the atomic structure which then alters the reflectivity of light of different wavelengths. (hmm too much physics? sorry lar)
anyway...
Nickel/Gold alloys are probably the cheapest to produce. However, nickel tends to result in skin irritation and allergy. (that's y some pple can only buy nickel free jewelleries). Cos of this problem, nickel/gold alloys arent quite the best type of white gold available. Even then, you might like to know that most American and Italian white gold alloys use nickel.
Palladium, a close relative to platinium, is also a very good metal to use for making white gold. Unfortunately, it is also very expensive. Also, it has a very high melting point. <-- not too gd. Nonetheless, palladium/gold alloy is IMHO better bah. Afterall, no nickel means almost everyone (who has money) can wear it without worrying abt skin allergies. ^^
*****Besides white gold, there is also other colors of gold alloys~
There's Blue gold: Gold / Iron alloy
Green gold: Gold with a high proportion of Silver or Cadmium
Pink gold: 50% Gold, 45% Copper and 5% Silver
White gold: see above. other possible metals include copper, tin, manganese-nickel
Yellow Gold: 50% Gold, 25% Silver and 25% Copper (hmm i wonder wat the diff is..)
Purple Gold: ~79% Gold and 21% aluminium
and last but not least, Black gold
Black gold can be made by many different methods too.
Electrodeposition using black rhodium or ruthenium is one method. Amorphouse carbon is also used at times, with the Plasma Assisted Chemical Vapour Deposition process. Controlled oxidation of carat gold containing chromium or cobalt can also be made to yield black gold. Ruthenium containing, electroplating solutions give a slightly harder black coating as compared to electroplating solutions that contain rhodium.
(wah. lookie cheem words above! oh boy oh boy... =p)
Heard from someone that a very very thin sheet of gold appears pinkish... Cant find any sources that confirms this piece of information as yet... Anyone care to clarify?
however, what i did find out about very thin sheet of gold is that they actually transmit a greenish tint of light. go figure out why urself. then come back and let me noe. =)
Actually if you are taoist, and burn those paper money during the seventh month (ghost festival), you can actually tear a bit of gold foil off one of those paper and look at the light passing through that foil... I remember doing it before and ya.. the light is greenish. ^^ (by the way, i'm not a taoist)
and that ends today's trivia. This session has been brought to you by xae after
booty and I started a conversation about 'what composition white gold has' on the mrt whilst going home.