The History of Johnson Matthey
Founded in London in 1817, Johnson Matthey became one of the world's most trusted names in precious metals. The company was appointed official refiner and assayer to the Bank of England and built a global reputation for quality that spanned two centuries.
JM established refineries worldwide, with their Salt Lake City facility becoming the primary source for American JM silver bars. These US-made bars, produced from the 1970s through 2015, are the most common JM bars in the American market.
In 2015, JM made a strategic decision to exit precious metals refining, selling the division to Japan's Asahi Holdings. This move instantly transformed all existing JM silver bars into finite collectibles that can never be reproduced.
JM Bar Types by Origin
Johnson Matthey operated refineries in multiple countries. Each produced slightly different bar designs that collectors now categorize:
| Origin | Characteristics | Collector Value |
|---|---|---|
| Salt Lake City, USA | Pressed bars, distinctive JM logo, most common in US | Standard premium |
| Canada (JM Canada) | Both pressed and poured bars, maple leaf designs | Higher premium |
| United Kingdom | Original hallmarked bars, oldest designs | Highest premium |
| Poured Bars (Any Origin) | Hand-poured with unique characteristics | Highest premium |
JM Value Guide by Size
| Size | Premium Range | Availability | Notes |
|---|---|---|---|
| 100 oz Pressed | 8-15% over spot | Common | Best value for serious collectors |
| 100 oz Poured | 20-40% over spot | Uncommon | Highly sought after |
| 10 oz Pressed | 10-20% over spot | Common | Popular size for collectors |
| 1 oz Bar | 25-50% over spot | Rare | Very collectible |
| Vintage/Early Bars | 50-100%+ over spot | Very Rare | Authentication essential |
Authentication Tips
Counterfeits exist, particularly for rare varieties. Here's how to verify authentic Johnson Matthey silver:
Authentic Features
- Distinctive JM logo (varies by era)
- Serial number (unique to each bar)
- Correct font styles for production era
- ".999+ FINE SILVER" marking
- Proper weight and dimensions
Warning Signs
- Incorrect logo or font style
- Missing or illegible serial number
- Suspicious pricing (too good to be true)
- Unknown seller, no return policy
- Weight or dimension discrepancies
Sigma Testing
For valuable JM bars, consider Sigma Metalytics testing. This non-destructive method verifies the internal composition matches the surface markings. Many dealers offer free testing, or you can purchase a home unit for serious collecting.
JM vs Other Vintage Refiners
| Refiner | Production Ended | Collectibility | Typical Premium |
|---|---|---|---|
| Johnson Matthey | 2015 | Very High | 10-30%+ |
| Engelhard | 1988 | Very High | 10-100%+ |
| Republic Metals | 2018 (bankruptcy) | Moderate | 5-10% |
| Sunshine Mint | Still Producing | Current | 3-8% |
Current Availability
JM bars appear regularly on the secondary market. Here are the best sources:
- Major Bullion Dealers - APMEX, JM Bullion, and SD Bullion occasionally stock JM bars
- eBay - Large selection, but verify seller ratings and return policies
- Local Coin Shops - May have JM bars in estate collections
- Auction Houses - Heritage Auctions for rare varieties
- r/Pmsforsale - Reddit precious metals community for peer-to-peer sales
When buying, prioritize reputable sellers and don't be afraid to pay for authentication on valuable pieces. The collector premium is only worth paying for verified authentic bars.