Gold Purity

Dears I want to calculate the purity of the gold. Plz tell the formula to calculate the purity.
Zalmey

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Zalmey wrote:

I hope you don't expect to calculate what can only be measured. Gold used in jewelry and other ornamentation is measured in karats. Pure gold is 24 karat, or 24 K. 75% gold is 18 K, 50% is 12 K, and so on. The karat number is rounded up in much commercial practice, so a lot of 14 K jewelry is in fact only 9/16ths gold.
These ratios are by weight. Since gold is significantly heavier than most of the metals it is commonly alloyed with, a piece of 14 K jewelry is noticeably larger than an 18 K piece of the same weight.
Jerry
--
Engineering is the art of making what you want from things you can get.

  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Jerry Avins wrote:

gold
14 K

jewelry
get.

Thanx for the reply but i want to determine the purity by myself. i.e. using some formula. plz help me in this way. thanx again in advance.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Zalmey wrote:

Please read the first line of my first answer, reproduced above.
Suppose that you want to determine the value of a resistor whose markings have worn off. It should be clear that you can't just use a formula to determine its value; you have to plug the results of a measurement into whatever formula you use.
Gold is commonly alloyed with many different metals, the choices differing from use to use. Among the alloying elements are copper, silver, nickel, zinc, platinum, and iron. Since these elements differ widely in weight, density (specific gravity) is not a useful indicator of gold content.
In commerce, gold is commonly tested by abrading a tiny amount on a ceramic block and treating the resulting mark with various reagents (the so-called "acid test"). The way that the mark reacts can provide a rough assay. Here are traditional instructions for a quantitative assay:
"To find the number of karats in a gold object is not as easy as testing for gold content. First, weigh the gold object. Then break it up and mix it with seven times its weight in silver. Beat this mixture into thin leaves and then add nitric acid. The silver and copper will dissolve. Now fuse the remaining gold and weigh it. Compare the first and last weights: the difference will be equal to the number of karats of pure gold. Repeat several times to check." A mass spectrometer works, as does electron-beam X-ray spectrometry. Whatever, you need a measurement.
Jerry
--
Engineering is the art of making what you want from things you can get.

  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.