Prehnite Jewelry in Bangkok

Prehnite is the color of a green grape held up to the sun: a soft, pale apple green with a gentle glow that seems to come from inside the stone. It is translucent rather than clear, so it looks calm and milky instead of sparkly, and some stones carry fine dark needles of another mineral that look like pencil strokes in green jelly. It is a quiet, fresh stone that suits silver and yellow gold equally well. We set natural prehnite in 925 sterling silver and solid gold at our studio on Sukhumvit 71, Bangkok.

This page covers what prehnite is, prehnite with epidote needles, how it compares with peridot, moonstone and tsavorite, how to wear and care for it, what makes a good stone, where it comes from, how to see the stones at our shop, and how to order in Bangkok or anywhere in Thailand.

What prehnite is

Prehnite is a calcium aluminum silicate that forms in cavities and cracks in volcanic rock, often next to zeolites. It rarely grows as single large crystals. Instead it builds up as rounded, bubbly masses made of countless tiny crystals packed together, and that structure is what gives it its soft, misty glow.

It is named after Hendrik von Prehn, a Dutch officer who brought samples back from the Cape of Good Hope in South Africa in the late eighteenth century. It was one of the first minerals ever named after a person. For a long time it was mostly a collector’s mineral, and it has become a popular jewelry stone only in recent decades, as more clean, gem quality material has reached the market.

Prehnite is usually not treated. Its color is natural, and every stone we set is natural, prehnite included. If a stone has had any treatment we tell you before you order.

Prehnite facts at a glance

• Family: calcium aluminum silicate, found with zeolite minerals
• Color: pale apple green to yellowish green, sometimes yellow or almost white
• Hardness: 6 to 6.5 on the Mohs scale
• Treatment: usually not treated
• Best for: pendants, earrings and bracelets; rings with care
• Care: warm soapy water and a soft cloth; no ultrasonic or steam cleaners
• Price: depends on the quality and carat you choose; we quote before you order

Prehnite with epidote

Some of the most striking prehnite contains thin black or dark green needles of a mineral called epidote. They run through the pale green stone in straight lines, sometimes crossing each other, sometimes radiating from a point. No two stones show the same pattern, and a well placed cluster of needles turns a simple cabochon into a small piece of natural art. Much of this material comes from Mali and Australia.

Clean prehnite without needles has a different appeal: an even, glowing green that looks like sea glass or green tea jelly. Neither is better. Some people fall for the pattern, others for the pure color, so it is worth seeing both before you choose.

Because of its milky green color, prehnite is sometimes mistaken for jade or for green chalcedony. They are different stones, and we always tell you which stone you are buying.

Prehnite and other green stones

Peridot is a clear olive to lime green gem that is faceted to sparkle. Prehnite is softer in look, translucent and glowing, with a cooler, paler green. If you want sparkle, choose peridot; if you want a gentle, misty green, choose prehnite.

Moonstone shares the same calm, inner light, but in white, peach or gray with a floating blue sheen. The two look lovely together in a pair of earrings or a layered necklace.

Tsavorite is a vivid, bright green garnet, rare and brilliant. Prehnite is its gentle opposite: pastel, relaxed and easy to wear in larger sizes.

How to wear and care for prehnite

At 6 to 6.5 on the Mohs scale, prehnite is a little softer than quartz. Its compact structure makes it reasonably tough, but a hard knock can still chip the edge of a cabochon, and over the years dust and daily wear can dull the polish. It is ideal for pendants, earrings and bracelets. A prehnite ring works well with a smooth cabochon in a bezel setting that protects the edges; take it off for the gym, cleaning and gardening.

Clean it in warm soapy water with a soft cloth, then rinse and dry. Keep it away from ultrasonic and steam cleaners, sudden heat, acids and strong household chemicals. Store it apart from harder gems such as sapphire and diamond so it does not get scratched. If it ever needs a polish or a check of the setting, bring it to our shop. Maintenance is free on jewelry we made.

What makes a good prehnite

Color comes first. The most loved stones are an even, fresh apple green or a slightly yellowish green. Very pale or grayish stones look flat; a richer green has more life.

Translucency gives prehnite its glow. Look for a stone that lets light into it so it seems lit from inside, rather than one that looks chalky.

Inclusions can be a plus or a minus. Neat, well spread epidote needles add character. Cloudy patches, cracks or brown spots usually take away from the stone.

Cut is usually a smooth cabochon, which shows the glow best. Prehnite is also cut as briolettes, drop shaped stones covered in small facets, which make beautiful earrings, and as beads. Clean, more transparent pieces are sometimes faceted.

Where prehnite comes from

Prehnite is found in Australia, Mali, South Africa, where it was first described, China, India and the United States, as well as in Scotland and other parts of Europe. Mali and Australia are best known for prehnite with epidote needles, and Australia also for fine clean green material. If you want to know the origin of a particular stone, ask us: we offer certified stones, and an uncertified stone can be sent to a gem lab for a report at extra cost.

See prehnite at our shop in Bangkok

Prehnite looks very different under shop lights, in daylight and on your skin, so it is worth seeing in person. If you tell us ahead that prehnite is the stone, we will have several ready, both clean green stones and ones with epidote needles, in cabochons and briolettes.

Walk in any time we are open, or book ahead so Yaron is there to help with the stone, the design and the metal, from 925 silver and gold plating to solid 9K, 14K or 18K gold.

Some prehnite with epidote has a pattern so special that you may want to keep it just as a stone. Loose prehnite is for sale with no jewelry order needed, and when you are ready we can turn it into a pendant or a pair of earrings.

Not in Bangkok? Message us and we will send photos and prices of the prehnite we have.

Prehnite questions we get

Is your prehnite natural?

Yes. Every gemstone we set is natural, prehnite included, and prehnite is usually not treated. If a stone has had any treatment we tell you before you order. We are a member of the Thai Gem and Jewelry Traders Association.

What are the black needles in prehnite?

They are crystals of epidote, another natural mineral that grew together with the prehnite. They are not a flaw, and many people choose prehnite for exactly these patterns.

Is prehnite the same as jade?

No. Prehnite is a different mineral, although its milky green color can look similar. We always tell you which stone you are buying.

Can I wear a prehnite ring every day?

With care. Prehnite is 6 to 6.5 on the Mohs scale, so a smooth cabochon in a protective bezel is best, and take the ring off for the gym, cleaning and gardening. Pendants and earrings are the easiest way to wear it daily.

How much does prehnite jewelry cost?

It depends on the quality and carat of the stone you choose, and on the metal. We give you the price before anything is made.

Can I buy just the stone?

Yes. A prehnite can be bought by itself, without a setting. If you want it made into a pendant or earrings, now or later, we are happy to set it.

How long does a prehnite piece take?

7 to 10 working days from your order, because the stones are already here in our shop, then 1 to 3 working days for delivery inside Thailand. We also ship abroad by FedEx.

Every prehnite piece is made to order by our team in Bangkok in 925 sterling silver or solid gold, with a 3-year warranty, free maintenance and free shipping across Thailand.