Question 1

Is spinel a rare gemstone?

Accepted Answer

Gem-quality spinel in fine colours is uncommon, especially clean red, neon pink and cobalt blue stones above two or three carats. Smaller stones in greys, lavenders and paler pinks are more readily available. Scarcity depends heavily on colour, size and clarity, so it is better to judge each stone individually than to treat all spinel as equally rare.

Question 2

Is spinel usually treated?

Accepted Answer

Most natural spinel is sold untreated. Heat treatment is used on some material, and laboratories can often identify it through changes in the stone's spectroscopic features, although results are not always conclusive. For valuable stones, a report from a recognised laboratory is the most reliable way to confirm natural origin and whether there are indications of heating.

Question 3

What is the difference between spinel and ruby?

Accepted Answer

Ruby is red corundum, while spinel is a separate mineral with a different chemical composition and crystal structure. Ruby is doubly refractive and pleochroic, spinel is singly refractive and shows one colour from every angle. Both are coloured red by chromium and occur in the same deposits, which is why they were confused for centuries. A gemmologist can separate them easily with standard instruments.

Question 4

Is spinel durable enough for an engagement ring?

Accepted Answer

Yes. Spinel has a hardness of 8 on the Mohs scale, has no cleavage and is stable to light and normal heat, so it is well suited to rings worn every day. As with any gemstone, a protective setting helps guard against hard knocks, and cleaning with warm soapy water is sufficient for routine care.