What is Hallmarked Jewelry? Can you buy it in Sri Lanka

Hi Dr Shihaan,

Assaying is defined as the testing of precious metals to determine their purity.The precious metals usually referred to while assaying jewelry are sterling silver, gold and platinum.

After assaying, the article is “Hallmarked” to confirm the purity of the metal. Hallmarking involves punching with three or four symbols, each symbol giving specific information.

Hallmarking jewellery gives confidence and assurance to the buyer of the standard of purity of the precious metal.

The assay office in Sri Lanka was established in October, 1981. It sent officials to the London Assay Office to up-date their assaying techniques. At the moment the assay office is based in Colombo at the National Gem and Jewellery Authority office complex. They are hoping to open two new branches in Galle and Kandy.
The Sri Lanka Assay Office is a member of the European Assay Offices whose head office is based in Geneva, Switzerland. The assay office in Sri Lanka also has plans to join the hallmarking convention.
The services of the assay office is open to anyone who may or may not be in the jewellery sector. The assay office also issues certificates after assaying and hallmarking.[attachment=65]The Sri Lanka Assay Office AddressThe assay office is situated at the headquarters of the National Gem and Jewellery Authority25, Galle Face Terrace, Colombo 03.Tele: 2325364, 2329295,2320758, 2390645-8.

The charges for assaying are found at the following link to their website:http://www.srilankagemautho.com/st-srilankaassay.php

Analytical techniques used at the Sri Lanka Assay Office.

  1. Cupellation method ( fire assay)2. Potentiometric titration3. Atomic absorption spectrophotometry4. X-ray fluorescence spectro metry

There are some registered jewellery shops around the capital Colombo that sells hallmarked jewellery.
The standard of purity of precious metals is indicated by specific numbers and the order in which the symbols are stamped in a piece of hallmark jewellery, is as follows:
Precious Metal Purity or Fineness
Sterling Silver 925
22kt.gold 916
18kt.gold 750
14kt.gold 375
The authorized standards of fineness in respect of gold, silver and platinum are given below:
Silver 999PPT925PPT800PPT

Gold 999PPT corresponding to 24Kt.916.6PPT corresponding to 22Kt.875PPT corresponding to 21Kt.750PPT corresponding to 18Kt.585PPT corresponding to 14Kt.417PPT corresponding to 10Kt.375PPT corresponding to 09Kt.333PPT corresponding to 08Kt.


Gold/Platinumassay office mark,gold/platinum mark,numerical purity value andmanufacturers mark.

Sterling Silverassay office mark,sterling silver mark,numerical purity value andmanufacturers mark.
Attached files

I thought hallmark jewelry means a logo by the manufacturer. I did not know that the same logos are used for one country by an office after testing and certifying.