Crystals Tips Blog

Sunstone is one of the most cheerful stones you can own: warm, golden and lit from within by a glittery shimmer that seems to catch the light as you turn it. That sparkle has a real, physical cause, and it is also at the heart of the most common mix-up in the trade, with a man-made glass called goldstone. This guide explains what sunstone really is, what creates the shimmer, its colours and types including prized Oregon sunstone, how it differs from moonstone and goldstone, and how to care for it.

What is sunstone?

Sunstone belongs to the feldspar family, the same broad group as moonstone and labradorite. What sets it apart is its warm body colour, from champagne and gold to orange and red, combined with a metallic glitter. It was named simply for that sunny, sparkling look. Most sunstone is a plagioclase feldspar, and the finest natural copper-bearing material, known as Oregon sunstone, is the official gemstone of the US state of Oregon.

Like other feldspars, sunstone is moderately hard at 6 to 6.5 on the Mohs scale, and it has cleavage, meaning it can split or chip along certain directions if knocked hard. That makes it durable enough for jewellery but worth handling with a little care.

What causes the sparkle?

The shimmer in sunstone is called aventurescence, and it is caused by countless tiny, plate-like inclusions inside the stone. As light hits these flat little mirrors it bounces back, creating a glittering, metallic sheen that shifts as you move the piece. In common sunstone the flecks are usually hematite or goethite, giving a reddish or golden glitter. In Oregon sunstone they are microscopic plates of copper, which can produce a particularly bright schiller, and copper can also colour the stone itself red or green. It is the same effect that gives aventurine quartz its name, but in sunstone the host is feldspar, not quartz.

Types and colours

There are two broad kinds of sunstone:

• Common sunstone, found in India, Norway, Canada, Russia and Tanzania, usually golden to orange or red-brown with a hematite or goethite glitter.
• Oregon sunstone, a natural copper-bearing feldspar from the USA, which can be colourless, champagne, pink, red, green or bicolour, and is valued for being untreated.

Across both, the colours run from pale champagne and warm gold through peach, orange and red, with green appearing in copper-rich Oregon material. Because the schiller and colour vary from piece to piece, every sunstone is a little different. See the range in our sunstone collection.

Sunstone, moonstone and goldstone

Three names get tangled together, so it helps to keep them straight. Moonstone is sunstone's cousin, another feldspar, but it shows a soft, billowy blue or white glow (adularescence) rather than a metallic glitter; you can browse it in our moonstone collection. Sunstone shows that sparkling, metallic schiller. Goldstone, despite the name, is not a stone at all: it is man-made glass with copper flecks, covered in the next section. In short, moonstone glows, sunstone glitters, and goldstone is glass.

Real sunstone vs man-made goldstone

The biggest thing to watch for is goldstone. It is a manufactured glass, made by melting copper into molten glass so it sets as glittering flecks. It is attractive and inexpensive, and there is nothing wrong with owning it, but it is not sunstone, and it should never be sold or priced as a natural stone. A few tells:

• Too-perfect glitter. Goldstone has a very even, dense, uniform sparkle. Natural sunstone's schiller is patchier and shifts in distinct flashes.
• Uniform colour. Goldstone is one even shade throughout; real sunstone usually varies across the piece.
• Bubbles and warmth. Like other glass, goldstone can contain tiny round bubbles and feels warmer and lighter than stone.
• Disclosure of treatment. Some red feldspar on the market is colour-treated; a good seller will tell you whether a stone is natural or treated.

For more general checks, see our guide on how to tell if your crystals are real and our note on goldstone in the aventurine guide.

Durability, care and water

Sunstone is reasonably durable but not bulletproof. At 6 to 6.5 on the Mohs scale it is harder than glass but softer than quartz, and because feldspar has cleavage it can chip or split on a sharp knock, so it sits in the middle of our guide to the most durable gemstones for everyday wear. It is fine for everyday pieces with a little care.

To look after sunstone: clean it with a soft cloth and a quick rinse or mild soapy water, then dry it; avoid ultrasonic and steam cleaners, which can worsen any internal flaws; and keep it away from hard knocks, harsh chemicals, perfume and prolonged heat. Store it apart from harder stones so its polish is not scratched, and choose protected settings for rings. See our water-safe crystals guide and how to store crystals.

How to choose sunstone

Sunstone is chosen on colour and sparkle. Look for:

• A schiller you love, bright, lively flashes that move across the stone.
• A warm body colour, from champagne and gold to orange, red or copper-bearing green.
• Honest labelling, natural sunstone versus goldstone glass, and any colour treatment disclosed.
• A practical setting, since sunstone has cleavage; protected settings suit rings best.

Frequently asked questions

Related reading

• Aventurine vs man-made goldstone glass
• Labradorite: another feldspar with an optical effect
• Are my crystals real? 7 simple checks
• Water-safe crystals guide
• How to store crystals