This calculation will hold true to all jewelry that is not mounted or attached with stones, pearl, ornament, etc.. First you must know how much the price of gold for today. We can go to www.kitco.com/gold.live.html, Kitco Inc.-Gold & Precious Metal Price Update or www.cnnfn.com/markets/commodities.html, CNNfn- Commodities Stock. From Kitco (October 20, 1996), gold is quoted at US$ 379.95 per ounce. One US$ = 26.265 Philippines Pesos (October 20, 1996). We first convert the price of gold to Philippines Pesos. 379.95 X 26.265= P 9979.38 per ounce. Next convert them to gram, from above information, one ounce equal 31.1 grams. P 9979.38/31.1= P320.88 per gram.
P 320.88 is the cost of gold per gram minus profit. So you ask how about 18K or 20K and so on. Well it is easy, first determine how must 24K gold is contain in 18K gold. 18/24 = .75. Next P 320.88 X .75 we get an answer of P 240.66/gram for 18K. For the price above you must add about 5 to 10% for losses occur during the making of gold into jewelry (some gold become dust or minute particles that jeweler can not able to recover them) and add some more for the cost of silver and copper too. Silver and copper cost so little that we often ignore their price in computation. So that's it, P 336.92 to P 352.96 per gram for 24K gold, of course this does not include the jewelry store's profit yet.
Let say one jewelry store sell for P 355 per gram for 24K and you choose a 24K bracelet that weigh 35.8 grams. How much will you pay for it? 35.8 grams X 355 = P 12,709. Some store add labor for the bracelet they sell, let say P 300, so P12,709 + 300, we get 13,009 for the price of the bracelet. The one who sell it without labor added will quote a higher price per gram compare to those without labor. Labor goes to the pocket of goldsmith who make them from gold bar to finished product. Which is cheaper? It's almost the same just don't exceed 50 or 100 grams and there is a big difference. Here the one with additional labor will be cheaper. For imported one that sold here in the Philippines, there is a lot of plus, plus. But if you go directly to the country you are interested, the above computation still applied but with slight variation.
Source - WEB