The Lapidary Arts
From: Wikimedia – Lapidary
Lapidary (from the Latin lapidarius) is the practice of shaping stone, minerals, or gemstones into decorative items such as cabochons, engraved gems, and faceted designs. A person who practices lapidary is known as a lapidarist. A lapidarist uses the lapidary techniques of cutting, grinding, and polishing.
The Rock Tumbling Hobby Forum has community members who are knowledgeable about all facets of the lapidary arts and more.
The tumbling of rocks is a lapidary technique where rocks of similar hardness are loaded into a barrel, usually made of rubber, along with an abrasive grit and water. Using either a rotary or a vibration machine, the rocks move and rub against each other as they progress through various stages of grit; thereby, smoothing and polishing is achieved.
In simple terms, a cabochon is a polished rock with a flat back side and a domed top side. Creating cabochons to be used as wearable jewelry can be accomplished equally well using a wide variety of tools. Most of the methods of creating cabochons involve using lapidary saws and grinding wheels to form the rough shape.
Polished rock spheres vary in size from tiny marbles to gigantic public statues. Creating spheres from rock starts with precise symmetrical cuts on a lapidary saw to form a rough sphere, followed by specialized machinery that typically applies a three-point hold by rotating ‘cups’ charged with progressive levels of abrasive grit until a perfect polish is achieved.
Rocks can be enjoyed as specimens in their original form, or they can be cut and polished for display. Cutting and polishing specimen rocks is typically achieved using a lapidary saw, followed by flat polishing equipment, either rotary or vibration. Often the weight of the rock holds the flat side of the stone down against a surface charged with abrasive grit.
A faceted gemstone is achieved through the symmetrical grinding of flat faces around the stone and is typically reserved for precious stones such as emeralds, sapphires, and diamonds. Faceting involves precise calculations to achieve a perfectly shaped gemstones, while also stepping through progressively smaller abrasive grit sizes to achieve a glass-like finish.
Shaping rocks using hand tools is a fine-art skill thousands of years old. Carvings can be as tiny and elegant as a cameo worn in a ring or locket, or as massive as statues on display in a park. Carvings created to be worn as jewelry typically feature a raised-relieve method in which background rock is carved away giving the appearance of an image rising from the stone.