Moonstone vs Opalite

Moonstone is orthoclase feldspar built in alternating microscopic layers, and where those layers approach the wavelength of light, scattering sends a blue-white billow rolling under the surface, the effect mineralogy calls adularescence. Sri Lanka's gem gravels supply the finest blue-sheen material, Art Nouveau master Rene Lalique set it into museum pieces, and the modern handbooks, Judy Hall's Crystal Bible among them, keep it filed where the old lapidaries did: new beginnings, intuition, the tides of feeling.

In my practice, Moonstone belongs to anyone tracking a cycle: a new month, a new habit, recovery milestones, the moon itself. Hold it through one full lunar month and notice which nights you reach for it. At Mohs 6 with easy cleavage it prefers pendants and pouches to daily rings, and at $12 to $28 for honest tumbled stones, it costs real but reasonable money.

For a deeper profile of this stone, see the full Moonstone page.

Opalite, as sold today, is man-made opalescent glass, and I say that in the first sentence on purpose, because it is so often labeled sea opal, opal moonstone, or simply moonstone. Ultrafine particles dispersed through the melt scatter blue light back to the eye while letting amber pass through, the same physics that blues the daytime sky, which is why Opalite glows cool from one side and warm from the other. Under a loupe, round gas bubbles betray the furnace; no natural opal or moonstone shows them. No nineteenth-century lapidary ever wrote about it, because it did not exist; whatever meanings Opalite carries are modern, made by the people who use it.

And yet I keep Opalite in my own collection, labeled honestly. Many people find its soft, even glow genuinely soothing, a night-light of a stone for transitions and gentle calm, and at $6 to $22 it asks little. The offense was never the glass; it is the lie on the label.

For a deeper profile of this stone, see the full Opalite page.