The Complete Guide to Silver Purity & BIS Hallmarking (999 vs 925)
1. The Four Standard Silver Grades in India
Silver in India is categorized under Bureau of Indian Standards (BIS) specifications into four recognized purity grades. Knowing which grade applies to your intended purchase is vital to prevent overpaying for alloyed metal.
| Grade Name | Fineness (Purity) | Composition | Primary Use Cases |
|---|---|---|---|
| 999 Fine Silver | 99.9% Pure | 0.1% Trace elements | Bullion bars, 1 kg trade bricks, puja coins, and raw investment bullion. |
| 925 Sterling Silver | 92.5% Pure | 7.5% Copper / Zinc alloy | Jewelry, rings, bracelets, designer silverware, and export tableware. |
| 900 Coin Silver | 90.0% Pure | 10.0% Copper alloy | Traditional Indian commemorative coins, historic rupees, and heavy idols. |
| 800 Silver | 80.0% Pure | 20.0% Base metal | Heavy traditional utensils, lamps (diyas), and decorative display items. |
Purity Tip: 999 pure silver is naturally too ductile and soft for wearable jewelry—it bends under mild finger pressure. For bracelets, chains, and anklets, 925 Sterling Silver is the worldwide standard because the 7.5% copper alloy provides essential structural rigidity and scratch resistance.
2. BIS Hallmarking for Silver: What to Look For
Under Bureau of Indian Standards (IS 2112:2014), genuine hallmarked silver articles in India must carry distinct laser-engraved identification marks:
1
The Official BIS Triangle Logo: A triangular mark signifying that the article has been tested and certified at an approved Assaying and Hallmarking Centre (AHC).
2
Purity / Fineness Grade: Engraved as
999, 925, 900, or 800 denoting the exact parts of fine silver per thousand.
3
6-Digit Alphanumeric HUID: Each hallmarked piece receives a unique 6-digit identifier (e.g.,
SL7X92) laser-etched into the metal, giving each item a permanent tamper-proof digital fingerprint.
3. How to Verify Silver on the BIS Care App
Any Indian consumer can independently verify their silver jewelry or bullion within 30 seconds using the Government of India's official mobile portal:
- Download the free BIS Care App (Android / iOS) developed by the Bureau of Indian Standards.
- Tap on "Verify HUID" on the homepage dashboard.
- Enter the 6-digit alphanumeric code stamped on your silver article and press Submit.
- The system displays the jeweler's registration number, the certified AHC lab name, the hallmarking date, and the verified purity grade.
4. Reliable At-Home Silver Authenticity Tests
While lab XRF spectrometry is the gold standard, three straightforward non-destructive physical tests help identify obvious silver counterfeits:
- Thermal Velocity (Ice Cube Test): Silver has the highest thermal conductivity of any natural metal (429 W/m·K). Placing an ice cube directly on a silver bar or coin will cause it to melt instantly, as if placed on a hot skillet, drawing heat rapidly across the surface.
- Neodymium Rare-Earth Magnet Test: Pure silver is diamagnetic and has zero attraction to magnets. If your silver article sticks or pulls firmly toward a magnet, it contains a high iron, steel, or nickel core.
- Acoustic Resonance (Ping Test): Tapping a genuine silver coin or bar produces a clear, high-pitched ringing sound that sustains for 2 to 3 seconds. Base metals like copper or lead produce a dull, dead thud.
Disclaimer: This guide is for educational and consumer awareness purposes only. Benchmark silver prices change daily during active trading hours on the MCX and local sarafa associations. Always verify the live benchmark rate on DailySilverPrice.today before confirming your purchase.