Citrine

Crystal system · Trigonal

Citrine is the yellow to amber-brown variety of crystalline quartz, colored by trace iron. Natural specimens are uncommon in nature, and most material on the market is heat-treated amethyst.

About Citrineextended article

Elemental Composition (by mass)
ElementMass %Visual
O Oxygen53.26%
Si Silicon46.74%
Computed from simplified end-member formula. Solid-solution series, water content, and trace substitutions cause real-world variation.
IMA Abbreviation (Whitney-Evans 2010)
Qz
→ Quartz
Variety of quartz
Standard symbol from American Mineralogist (Whitney & Evans, 2010). Used in thin-section labeling, phase diagrams, and IMA-style species records.
Pronunciation
/sɪˈtriːn/
sit-REEN
two syllables; French origin
Birthstone & Anniversary Gift Reference
November (zodiac)zodiac: Scorpio / Sagittarius
Luster
vitreous
Same as quartz parent.
Color Cause (Chromophore)
Chromophore:
Fe³⁺ + color center
Mechanism:
thermal alteration of Fe-bearing quartz
Color produced:
yellow
Natural or heat-induced; most market citrine is heated amethyst.
Diaphaneity (Transparency)
transparent
Gem-quality transparent.
Type Locality
Source: Variety of quartz
Specific Gravity
2.65
g/cm³
light
Same as quartz.
For comparison: water = 1.00, glass ≈ 2.5, quartz = 2.65, corundum ≈ 4.00, galena ≈ 7.50, gold ≈ 19.3.
Synthetics & Imitations
Lab-grown methods
Hydrothermal 1970
Lab citrine produced by Brazilian doping; standard market alternative is heat-treated amethyst.
Common imitations
Heat-treated amethyst
Most market "citrine" is heated amethyst — same species but heat-altered.
Yellow glass
Lower RI.
Geological Setting
Environment:
hydrothermal
Host rock:
basalt geode, pegmatite
Companions:
Natural citrine forms in similar settings to amethyst; most market citrine is heated amethyst.
Treatments & Enhancements
Heat-treated amethyst origincommonstable· detection: moderate
Most market citrine is heated amethyst (orange-brown tones). Natural citrine is rarer and more pale yellow.
As a buyer: request written disclosure of treatments and confirm whether the price reflects treated or untreated material.
Characteristic Inclusions
Tigerlike zoninggrowth-pattern★ diagnostic
Heat-treated amethyst-citrine shows zoned coloration; natural citrine is more evenly colored.
Diagnostic inclusions are characteristic enough to help identify origin or species under 10× loupe.
Pleochroism (dichroic)
Axis o
light yellow
Axis e
darker yellow
Strength: weak
Very subtle pleochroism; not a key ID feature.
Cleavage & Fracture
Cleavage:
none
Fracture:
conchoidal
No cleavage; conchoidal fracture as in all quartz.
Market availability: Common
Widely available in most dealer stocks. Specimens span all price tiers.
Collector tier: Solid Display
Reliable mid-tier display species. Easy to find in well-formed examples; broad locality diversity.
Mohs 7
Vickers (~) 1400 HV
Knoop (~) 1100 HK
Element composition by mass

Formula: SiO₂ (quartz var.) · molar mass: 60.08 g/mol

O 53.26%
Si 46.74%

Computed from atomic weights (IUPAC 2021). Site-occupancy groups (Fe,Mn) split equally.

GroupQuartz Group (silica)
Related members: Quartz · Amethyst · Rose Quartz · Chalcedony · Agate · Jasper
Mohs Hardness 7

Citrine sits at 7 on the Mohs scale — harder than glass; scratches steel.

Colors:
Streak
White
Crystal system
Trigonal
Oxides & HydroxidesOxides (Silica Group)
TL;DR · 1 min read
Citrine is the yellow to orange-brown variety of quartz, colored by Al³⁺ + Fe³⁺ + radiation defects. Most commercial citrine is heat-treated amethyst (the natural conversion is rare).

Citrine is the yellow to orange-brown variety of quartz, colored by Al³⁺ + Fe³⁺ + radiation defects. Most commercial citrine is heat-treated amethyst (the natural conversion is rare). Bahia and Minas Gerais (Brazil) produce iconic gem-quality citrine, often in bicolor “ametrine” zoned with amethyst from Bolivia.

More minerals to explore

About Citrine

Citrine is a variety of quartz (SiO2) whose color ranges from pale lemon yellow through golden honey to deep madeira brown. The color arises from trace ferric iron in the silicon dioxide lattice. Natural citrine forms in low-temperature hydrothermal veins and is geologically rare; the vast majority of commercial citrine is amethyst heated to roughly 470 degrees Celsius, which converts violet to yellow.

Identification & care

Citrine shows the same physical properties as other quartz varieties — Mohs hardness 7, specific gravity 2.65, vitreous luster, conchoidal fracture, no cleavage. Color is the primary indicator: a saturated yellow to brown without the reddish secondary tones of fancy topaz. Heat-treated specimens often show a slight reddish undertone and white tips where the original amethyst color was paler.

Collector context

Collector notes

Natural untreated citrine commands a substantial premium and is most often found in Brazil, Madagascar, and Russia. For collectors, the value triangle is color saturation, clarity, and crystal form. Sharp prismatic crystals with terminated points and clear evidence of natural growth (no signs of heating) are the most sought-after pieces. Always ask sellers about treatment provenance, since heat-treated citrine is universally accepted commercially but should not be sold as natural.