Difference Between Hallmarked, KDM & 916 Gold

Gold jewelry buyers often come up the terms like hallmark gold, KDM gold, and 916 gold, but many are unsure what they mean. These terms indicate purity, composition, and certification standards. A hallmark for gold ensures authenticity, while KDM refers to a specific soldering process. 916 hallmark gold represents 22K purity.

Identifying genuine gold requires checking the gold hallmark sign, which confirms its standardization. Understanding these classifications helps buyers make informed choices and avoid fake products. This webpage explains the differences, the significance of gold stamps and markings, and what to look for when purchasing gold.

Table of Contents:

• ⇾ Difference Between Hallmarked, KDM & 916 Gold
• ⇾ HallMarked Gold
• ⇾ KDM Gold
• ⇾ 916 Gold
• ⇾ Frequently Asked Questions

Difference Between Hallmarked, KDM & 916 Gold

Let us look at the difference between the hallmark, KDM & 916 Gold:

HallMarked Gold

Hallmarking is the process of certifying the purity and fineness of gold. Can you measure? Yes, It refers to gold that has been officially certified for purity and quality.

1. Authority & Certification
• The Bureau of Indian Standards (BIS) is responsible for hallmarking gold and silver jewelry under the BIS Act.
• Gold is tested and certified in BIS-assaying centers, with over 330 centers across India.
2. Hallmark Components (Laser-engraved on gold items)
• BIS Hallmark – Confirms that purity is verified in a licensed laboratory.

Gold Karat (K)	Purity Percentage	Fineness Number
22K	91.6% Pure	916
18K	75.0% Pure	750
14K	58.5% Pure	585

• Assaying & Hallmarking Centre’s Mark – Identifies the testing centre.
• Jeweller’s Identification Mark – Confirms the retailer’s certification.
• HUID (Hallmark Unique Identification Number) – A 6-digit alphanumeric code for authenticity.
3. Purpose & Importance
• Ensures gold quality and authenticity, preventing fraud.
• Mandatory for gold jewelry in many countries, including India.
• Helps in reselling as hallmarked gold retains its value.
4. Hallmark Variants in India
• 958 (23 Carat Gold)
• 916 (22 Carat Gold)
• 875 (21 Carat Gold)
• 750 (18 Carat Gold)
5. Precaution While Buying Gold
• Always check for hallmarking when buying from local or small retailers.
• Ensure the BIS logo, purity mark, jeweler’s mark, and HUID are present.

KDM Gold

It is an alloy of 92% gold and 8% cadmium, originally used for soldering gold jewelry. The term KDM comes from "Kadmium" gold, referring to the cadmium content in the alloy.

1. Purpose & Use
• Gold jewelry requires soldering, which joins different parts together.
• Traditional soldering used a gold-copper alloy (60% gold, 40% copper), which caused purity loss when melted.
• KDM soldering with cadmium prevented purity loss while allowing intricate designs.
2. Issues & Ban
• Cadmium exposure was found to be hazardous to artisans, leading to serious health risks.
• Due to these concerns, BIS banned KDM gold, and it is no longer legally certified.
• Modern gold jewelry now uses zinc or other safe metals for soldering instead of cadmium.
3. Current Status
• Even though KDM jewelry is no longer produced, the term is still widely used in the industry.
• KDM gold is not hallmarked, meaning its purity is not officially certified.
• Buyers should verify the BIS hallmark when purchasing gold instead of relying on the term "KDM".

916 Gold

It refers to 22-karat gold, meaning it contains 91.6% pure gold and 8.4% other metals like copper, silver, or zinc. The number 916 comes from the calculation 22K ÷ 24K = 91.6%.

1. Composition & Properties
• The remaining 8.4% of the alloy consists of metals that enhance strength and durability.
• Pure 24K gold is too soft for jewelry, so 916 gold is preferred for intricate designs.
• The added metals may also slightly alter the color of gold (e.g., zinc & silver can create a greenish tint).
2. Hallmarking & Identification
• BIS 916 hallmark gold ensures certified purity and authenticity.
• The hallmark typically includes:
• 916 or 22K stamp
• BIS logo
• Jeweller’s identification mark
• Assaying & Hallmarking Centre’s mark
3. Common Uses
• Jewellery & Ornaments – Preferred for its balance of purity and durability.
• Not primarily used for investment, as 24K gold is preferred for bullion and coins.
4. 916 Hallmark Gold Price
• 916 hallmark gold price varies daily based on gold market rates.
• 916 KDM gold rate differs as KDM refers to an older soldering technique and is not BIS-certified.