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Jewelry, Gems, & Minerals/Gold karat marks (not mfg marks)


garybeac wrote at 2011-12-10 23:20:13
Hi, We have a brooch that was custom made for my wife's grandmother in about 1925. She lived in Montgomery, Alabama. It is marked <D-M> and it appears to be at least 20 karat gold. It is set with six 1/2 karat and one 3/4 karat diamonds that look to be very good. The diamonds are surrounded with black stones (onyx?). The clasp is intricate, so it may be that this is one of those brooches that was also part of a necklace. Any ideas?  

Kaleigh Barrett Bushnell wrote at 2016-05-19 01:15:18
The stamp is most probably Indian but it's not a makers mark or stamp as the KDM stamp means that the Jewelry was soldered with Cadmium. Cadmium called 'Kadium' in some places and marked KDM was traditionally used in soldering of gold jewelry for its good properties of liquidity and melting at lower temperatures, which is not the case any more as Cadmium is known to create toxic fumes when melted, which are very dangerous to health, over a period of time and may be harmful to humans making the gold jewelry (Carcinogenic), some infact most countries have banned the use of Cadmium from use, from workshops. Jewelers in many parts of the world now use gold solders, which are free from Cadmium. Please note that the wearer of the gold jewelry is not harmed, this issue only concerns the manufacturing process however some people can have allergic reactions to the cadmium solder/bonds. Please google 22kdm to find anything else out I hope this helps.

Jewelry, Gems, & Minerals

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Have a question about jewelry repair or working with precious metal jewelry and gemstones? For many years up to December 31, 2010, I was a working professional bench jeweler, involved everyday with setting stones in mountings, designing and making jewelry, repairing and limited custom manufacture. If you work with jewelry as a hobby or as a profession, I might be able to help. I deal with the retail business, not mass production. Ask privately if you wish. See the box for that: It keeps your question between us. Please DO NOT ask MAKER'S MARKS, but metal quality marks are fine to ask. Please DO NOT ask diamond prices. See a gemologist for that.


I have extensive experience in design, service and making of jewelry. I deal mostly with precious metals and gemstones but work with many materials as needed and usable to create an artistic design. My experience also includes freelance photography and photographer of jewelry and similar items for a former employer and individuals. Design of custom items requires reading the desires of the client and being clear on what can be done within that framework...then fulfilling the transition of idea to reality. Effective communications is essential in a working designer/producer and customer relationship.

Education is English/Physics! Started in human resources, to advertising, to, what a road. I have had formal training in jewelry work and many shared experiences with top grade jewelers. We just never know were we will go or be. Follow your best, your dreams, with some discretion! Don't let the work tear up your body along the way as it has mine.

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