Understanding Metal Hardness

Today I'm sharing a Sea+Stone PSA to help you preserve your jewelry and ensure many years of enjoyable wear! You may have seen this clasp before:

We have used this hook clasp on so many of our silk-knotted gemstone necklaces over the years. We like it because it is secure, it is made of precious metal, and it is easy to put on without fumbling for tiny parts. This clasp, as well as most of the gold-colored components in our semiprecious line, is created with vermeil. Vermeil (pronounced ver-MAY) is a gold plated sterling silver. Unfortunately bending this hook open or pinching it shut can lead to cracks in the gold plating layer, or eventually a break in the silver metal beneath it!

We like to tell our customers to just "let it slide"! The hook will slide through the eye component and the weight of the gemstone beads will prevent the clasp from unhooking.

The sterling silver metal beneath our vermeil plating is considered work-hardened. This means that the metal has been shaped & hammered until it will very stubbornly hold its shape! We use work-hardened metal on things like clasps because security is so important, and we can't risk a hook bending enough to let your necklace slide open and off your neck.

When you shop for metal wire or sheet to use when creating jewelry, you will see that it comes in several hardness levels:  "dead soft" or "1/2 hard" or "full hard". This means that the metal is easier to bend, manipulate, & shape. Metal gets progressively harder and harder as you work with it. So "Dead Soft" is metal at its most relaxed state (speaking on a molecular level). The more stress you put on the metal by trying to form it into a piece of jewelry, the molecules get tighter and the metal becomes harder to work with.

This is why we use a process called annealing when making jewelry. Annealing a metal helps to restore it to a more relaxed form, and the way we achieve this is through heat.

Understanding metal hardness and the way it moves helps to better understand how to wear and preserve your jewelry!

Since we have used work-hardened metal on our clasps, our sterling silver is already as hard and molecularly tight as possible. Because of this, it does not have the flexibility to be bent. Any further manipulation of the metal at this state can cause it to crack or fully snap. Like people, too much stress means that it will bend until it breaks. So "let it slide" to keep your clasp intact and functioning properly!

***UPDATE - We have now switched to our new clasp as pictured here:

It is formed with wire, NOT CAST like our old style clasp. This allows the clasp to have a little bit more spring and give. While it still shouldn't be bent open and closed (we still encourage you to "just let it slilde")... it is more forgiving than our last style of clasp and so far NO reports of accidentally broken hooks!

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