Property Comparison

Property Citrine (Quartz) Topaz Diagnostic?
SG 2.63 – 2.65 3.49 – 3.57 Yes
RI 1.544 – 1.553 1.609 – 1.643 Yes
Optic Character DR U+ (uniaxial positive) DR B+ (biaxial positive) Yes
Hardness 7 8 Clue
Cleavage None Perfect (basal) Clue
Crystal System Trigonal Orthorhombic No
Birefringence 0.009 0.008 No
Fluorescence (LW) Inert Variable No
Luster Vitreous Vitreous No

The Definitive Tests

  1. Heft / specific gravity. SG is the fastest separator: topaz reads 3.49–3.57 against citrine's 2.63–2.65. On loose stones of similar size the difference is large enough to feel in the hand — topaz is noticeably heavier for its size. Hydrostatic weighing makes it unambiguous.
  2. Refractometer. Citrine reads 1.544–1.553; topaz reads 1.609–1.643. The ranges do not overlap, so a single clean reading settles the identification.
  3. Optic figure (polariscope). Both are doubly refractive, but citrine is uniaxial positive — quartz shows the characteristic 'bull's eye' optic figure — while topaz is biaxial positive. Useful confirmation when the stone is mounted and SG can't be measured.

Common Mistakes

Frequently Asked Questions

Is citrine a type of topaz?

No. Citrine is the yellow to brownish-orange variety of quartz; topaz is a separate species. Their properties separate cleanly: citrine RI 1.544–1.553 and SG 2.63–2.65 vs topaz RI 1.609–1.643 and SG 3.49–3.57. Citrine is one of the most common substitutes offered for yellow topaz, which is why the names get blurred in the marketplace.

What is the fastest way to tell citrine from topaz?

Specific gravity. Topaz (SG 3.49–3.57) is substantially denser than citrine (SG 2.63–2.65) — the difference is large enough that the heft test works on loose stones of similar size. A refractometer is equally decisive: the RI ranges (1.544–1.553 vs 1.609–1.643) do not overlap.

Is most citrine natural?

Most commercial citrine is heat-treated amethyst. Natural citrine is pale yellow and uncommon; the warm reddish-orange "Madeira-type" color typical of commercial material is produced by heating amethyst. Treated or not, it is still quartz — RI, SG, and optic character are unchanged, so the citrine vs topaz separation works the same way.

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