Is International Silver Company Real Silver?

Not sure if your International Silver Company flatware is solid sterling or just plated? Learn the difference, how to check hallmarks, and what each type is worth.

International Silver Company is a name that shows up at estate sales, antique stores, and in inherited tableware sets. Because "silver" is in the brand, many assume every piece is solid precious metal, yet that isn’t always true.

The firm produced both sterling silver and silver-plated items, and telling them apart can dramatically change the value of what you own. This guide explains the company’s history, how to read its hallmarks, and simple ways to confirm whether your piece is real silver.

A Brief History of International Silver Company

Founded in 1898 through the merger of more than a dozen New England silversmiths, International Silver Company (often stamped "I.S. Co." or just "International") became one of America’s largest makers of household silverware.

During the early 20th century the company operated multiple subsidiaries, Rogers, Simpson, Holmes & Edwards, and others, each targeting a different price point. That wide product range is why today’s collectors encounter everything from humble hotel flatware to ornate sterling tea services bearing the International name.

Sterling vs. Silver Plate: What Did International Silver Make?

International marketed two primary categories. Sterling items are 92.5% pure silver throughout, while silver-plated pieces have only a thin outer layer of silver over base metal such as nickel or copper.

The company’s high-end lines, Prelude, Spring Glory, Wild Rose, and Continental, for example, were produced in solid sterling. Mass-market patterns like Avon and DeSoto were offered only as plate. Because both lines shared similar styling, confusion is easy without checking the marks.

Hallmarks and Stamps to Look For

The fastest way to verify composition is to inspect the underside of flatware handles or the bottom of hollowware.

Genuine sterling items will always include the word "Sterling" or the numerical stamp "925" alongside the pattern name or the International logo. Silver-plated pieces, in contrast, read "I.S.", "International Silver Co.", "IS Co.", or a subsidiary name with no purity number.

Simple Tests for Verifying Silver Purity

If markings are worn or missing, a few non-invasive tests can help. A rare-earth magnet will not stick to sterling but may cling slightly to plated items if the base metal contains nickel. You can also perform an ice test: sterling conducts heat so well that an ice cube melts noticeably faster on a solid piece than on plated brass.

For absolute certainty, jeweler’s acid test kits or XRF (X-ray fluorescence) scans provide a definitive reading. Because acid can leave faint spots, always test an inconspicuous area or rely on professional appraisal equipment.

Current Market Value of International Sterling and Plate

Sterling flatware generally sells at or above its melt value, which fluctuates with the silver spot price. For reference, a 12-place setting of Prelude weighing about 70 troy ounces contains over $1,500 in silver at $22 per ounce, with additional premium for desirable patterns or excellent condition.

Silver-plated sets hold primarily decorative value. Most everyday patterns trade between $1 and $3 per piece, though ornate Art Deco or scarce hotel ware can bring higher prices. Complete, unused boxed sets draw the best offers.

Care Tips to Preserve Your International Silver

Whether sterling or plated, gentle care prolongs beauty and value. Hand-wash in mild detergent, avoiding citrus-based cleaners that can pit silver. Dry immediately with a soft cloth to prevent water spots.

Store pieces in tarnish-resistant chests or wrapped in acid-free tissue. For sterling, occasional polishing with a non-abrasive cream keeps oxidation at bay. Plated items require even lighter touch because aggressive rubbing can wear through the silver layer.

Final Thoughts

International Silver Company pieces can indeed be real silver, just not always. Understanding the difference between sterling and plate, recognizing hallmark clues, and using simple tests ensures you know exactly what you have.

Armed with that knowledge, you can price items confidently, care for them properly, and decide whether to keep, sell, or pass them on to the next generation.