There's a question that comes through my office door at least once a week, usually wrapped in a little velvet pouch and a lot of hope: "Is this a real ruby?"

The stone is red. Everyone in the family has always called it a ruby. But "red" and "ruby" are not the same thing — and after more than 40 years in this business, I can tell you that some of the most interesting stones I've ever identified started out mislabeled by the very families who loved them.

That's why I keep a gem laboratory in my office. I identify stones — I never guess.

Take the ring sitting on my bench this week: a stunning 14kt white gold cocktail ring with a 1.40-carat oval-cut red center stone, wrapped in a double halo of round brilliant diamonds totaling about 0.85 carats. Beautiful, confident, undeniably a statement. The listing calls it a natural ruby, and the color is that deep, saturated crimson that ruby lovers dream about.

But here's what you need to know: when a colored stone comes to me, the first thing I do is forget everything anyone has told me about it — including the price tag.

The gemologist's checklist

Ruby is the red variety of corundum, an aluminum-oxide mineral that also gives us sapphire in every other color. Corundum is a 9 on the Mohs hardness scale — only diamond is harder. That hardness is why rubies survive centuries of wear in estate pieces, and why they're one of the very few colored stones I'd call truly everyday-wearable.

But hardness alone doesn't tell me what a stone IS. Glass can be cut to look like anything. And laboratory-grown rubies — real corundum made by real people using the flame-fusion process since the early 1900s — are chemically, optically, and physically the same mineral as nature's work. There's nothing wrong with them. But they're not natural rubies, and they shouldn't be priced as if they are.

So here's my checklist — and it's the same checklist I'd run on any red stone you bring me:

1. Color. Fine ruby glows. The best stones have a vivid, slightly pinkish-red that gemologists call "pigeon blood" red. Too orange, too pink, or too dark and the stone may still be corundum — but the value shifts dramatically.

2. The microscope. This is where the romance of the story meets the science. Under magnification, a natural ruby almost always carries fine silk — tiny needle-like rutile inclusions that formed as the crystal grew in the earth over millions of years. Those needles are a stone's birth certificate: nature's signature that no laboratory can quite forge. (A romantic aside: some fine rubies are deliberately left unheated because their silk scatters light into a star — that's how star rubies are born.)

3. Refractive index. My refractometer measures exactly how the stone bends light — a numerical fingerprint. Ruby's range is distinctive. Glass, synthetic spinel, and garnet (a common "ruby lookalike" in older estate pieces) each bend light differently, and the numbers don't lie.

4. The synthetic tells. Lab-grown rubies carry their own birthmarks: the curved striations left by the flame-fusion process, tiny gas bubbles, or the veiled, fingerprint-like inclusions typical of flux-grown synthetics. I know exactly what to look for.

5. Treatments. Most rubies on the market have been heat-treated — a stable, permanent, industry-accepted enhancement that coaxes out color and clarity. Heat is normal. What matters is disclosure: a natural, untreated ruby of fine color is genuinely rare and commands a premium, so you deserve to know exactly what you're looking at.

Only when a stone passes every one of those tests does it earn the word "natural ruby" in one of my descriptions — not from an optimistic label, but from testing.

Why this matters for your jewelry box

Most people don't buy their rubies — they inherit them. And that's where my favorite part of this work lives: identifying heirloom pieces. That red stone in grandmother's ring might be a natural ruby worth real money. It might be a lab-created ruby from the 1940s, when laboratory-grown stones were popular in fine jewelry. It might be a garnet, a red spinel, or glass. Each of those answers changes what the piece is worth and what you should do with it — insure it, restore it, wear it joyfully, or pass the story along to the next generation.

You can't make a good decision about a stone until you know what it is. That's not just my philosophy — it's the whole reason my practice exists.

So the next time someone in your family pulls out a red stone and says, "This has always been called a ruby," smile — and then have it tested. The truth is usually more interesting than the family legend.

— Gina Watson, GIA Graduate Gemologist. In the jewelry business for over 40 years, serving Orange County since 1985.

Ready to know what you really own? Call for a private appointment: 📞 949-230-1069.