If you've ever seen a vintage brooch flash pink, blue and gold all at once, you've met aurora borealis. Collectors call it AB for short, and it's one of the easiest mid-century details to learn to spot.
What aurora borealis means
An aurora borealis rhinestone is a glass stone with a very thin metallic coating that splits light into shifting rainbow colors. The name comes from the northern lights. The coating can sit on clear stones or on colored ones, so you'll see AB in everything from icy clear to deep amber and topaz.
Where it came from
The finish was developed in the mid-1950s by Swarovski, the Austrian crystal maker, working with the fashion designer Christian Dior. Within a couple of years it had spread through the costume jewelry world, and it stayed in fashion into the 1960s.
How AB helps date a piece
Because the finish arrived in the mid-1950s, aurora borealis stones usually point to a piece made in 1955 or later. It's a helpful clue, not proof. Other iridescent finishes existed earlier, and AB stones are still made today. Look at the whole piece, including the construction, the clasp and any maker's mark, before settling on a date.
How to spot it
- Tilt the piece under a light. AB stones shift color as you move them, and plain stones don't.
- Check the settings. Prong-set stones are generally a sign of better-made costume jewelry than glued-in ones.
- Look for dark or cloudy stones, which can mean moisture has reached the foil backing.
Caring for aurora borealis jewelry
Keep it dry. Water and cleaning solutions can cloud the foil behind a rhinestone and wear the coating. Wipe gently with a soft dry cloth, put your jewelry on after perfume and hairspray, and store pieces separately so the stones don't scratch each other.
Shop aurora borealis
We currently have a rivoli flower cluster brooch with teal, pink and blue AB stones, a 1950s yellow and aurora borealis rhinestone brooch and an amber and AB rhinestone statement necklace. You can also browse our vintage rhinestone jewelry and mid-century jewelry for more one-of-a-kind brooches, necklaces and earrings. Every piece is the only one we have.