When buying gold in Kerala, you will hear the term 916 Gold frequently. However, older generations may still refer to KDM Gold. Understanding the difference between these terms is important, as one is the current industry standard and the other has been phased out due to health and quality concerns.
What was KDM Gold?
In traditional gold jewellery making, soldering is used to join different parts of an ornament. The solder alloy must melt at a lower temperature than the gold itself. Historically, jewellers used a mix of gold and Cadmium (ratio of 92% gold and 8% cadmium) as a solder. This type of gold became known as KDM Gold.
Why Cadmium Was Used Cadmium melted at a lower temperature, maintained the ornament's overall purity close to 22K, and did not tarnish easily.
The Problem with Cadmium During the soldering process, gold artisans inhaled toxic cadmium fumes, leading to health issues. Additionally, cadmium could cause skin irritation for some wearers. As a result, the Bureau of Indian Standards (BIS) banned the use of cadmium in gold soldering.
What is 916 Hallmarked Gold?
Following the phase-out of KDM, the industry transitioned to 916 Hallmarked Gold.
- The Meaning of 916: "916" indicates that the gold has a purity of 91.6% (which corresponds to 22 Karat purity).
- Modern Soldering Methods: Modern 916 jewellery is soldered using zinc or copper-based alloys that do not contain cadmium.
- Hallmark Verification: Purity is verified by government-approved assaying centers, which apply the BIS hallmark stamp.
Comparison Summary
The table below outlines the differences between these standards:
| Feature | KDM Gold | 916 Hallmarked Gold |
|---|---|---|
| Soldering Alloy | Cadmium (Toxic) | Zinc / Copper (Safe) |
| Purity Guarantee | Lacked official checks | Certified by BIS assaying |
| Legal Status | Phased out / Banned | Mandatory standard |
Why Check Before Buying
- Do Not Buy Old KDM Stock: Avoid purchasing un-hallmarked gold jewelry, as it may be older stock containing cadmium.
- Check Purity Marks: Ensure your purchase bill lists the BIS hallmark and HUID code.
- Compare Daily Rates: Check today's 22K (916) gold rate on RateTracker.in to ensure you pay the correct market price.
