About this stone
Color
RedPink-RedPurplish-Red
Origin
Burma/MyanmarMozambiqueMadagascarThailandIndiaSri Lanka
Mohs hardness
9
Treatment categories
HeatedNatural/Unheated
Industry-standard treatment
Heat treatment
Mineral chemistry
Aluminum oxide (corundum) colored by chromium
Crystal system
Trigonal
Stone family
Corundum
Birthstone
July
Common cuts
Faceted RondelleRoundSmoothMicrofaceted Round
Common sizes
2mm3mm4mm6mm
Care notes
Extremely durable. Heated and unheated tolerate ultrasonic and steam; lead-glass-filled and fracture-filled material does not — confirm treatment before aggressive cleaning.
Related stones
Sapphire, Spinel, Garnet
Frequently asked questions
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Is your ruby real, or is it lead-glass-filled?
Ruby is corundum colored red by chromium. The dominant counterfeit problem in the bead trade is lead-glass-filled ruby — fractures filled with leaded glass to make low-grade rough look better — plus beryllium-diffused and fracture-filled material at the lower price points. Those are different commercial categories from natural or heat-treated ruby. Treatment category should be disclosed (Heated, Natural / Unheated, Glass-Filled, Diffused) — ask before buying if a strand doesn't specify. -
Is the ruby heated?
Almost all bead-grade ruby is heat-treated. Heat treatment is permanent, stable, and the industry-standard treatment for ruby — it's not a quality knock, but it is information you should have. Treatment status should be disclosed; strands marked "Natural" or "Unheated" are the smaller untreated tier and are priced accordingly. Ask before buying if the page doesn't specify treatment. -
Why is your bead-grade ruby less expensive than I expected?
Bead-grade ruby is a different category from gem-grade ruby. The transparent, eye-clean ruby cut for fine jewelry is a fundamentally rarer material than the opaque-to-translucent rough used for bead strands. Bead-grade ruby gives designers access to corundum at sizes (2mm–6mm) and per-strand prices that work in production. Bead-grade and gem-grade are different products that share a mineral, not one being a discount on the other. -
What's the difference between Burmese and Mozambique ruby?
Burmese (Mogok) ruby is marble-hosted, low-iron, and shows the classic "pigeon's blood" red with a slight bluish undertone and strong red fluorescence under UV. Mozambique (Montepuez) ruby is amphibolite-hosted, higher-iron, and tends to a deeper saturated red with sometimes more purple or pink undertone and weaker fluorescence. Burmese carries the weight of the historical-source story and the color register; Mozambique offers comparable material at broader availability. -
How do I tell if a ruby is real?
Practical signals: weight (real ruby is dense; plastic and resin imitations feel light), hardness (Mohs 9 — won't scratch with a steel pin), color depth under different light sources (real ruby holds color in incandescent and natural light; some imitations shift), and price floor (any ruby strand priced like glass beads probably *is* glass beads). Lead-glass-filled ruby is harder to spot without magnification — under 10x loupe, look for blue/orange flashes in surface-reaching fractures and trapped air bubbles. The most reliable signal is buying from a seller that discloses treatment per SKU.