Tangerine Quartz Identification Guide
Identify orange iron-coated tangerine quartz crystals, confirm the surface stain, and separate them from citrine and dyed quartz.
Read the full Tangerine Quartz encyclopedia entry →
What Tangerine Quartz Looks Like
Tangerine quartz is ordinary quartz (often clear or milky) whose surface is coated or stained orange to rusty-red by a thin film of iron oxide (hematite/limonite). The color is a surface phenomenon, not internal pigment, distinguishing it from citrine.
- Color: orange, peach, to rusty-red exterior; the quartz beneath is colorless or white.
- Luster: vitreous (glassy); the iron film can look slightly earthy/matte.
- Transparency: transparent to translucent; you can often see clear quartz under thin coatings.
- Crystal habit: hexagonal prisms with pyramidal terminations, single points or clusters.
Step-by-Step Field ID Checklist
- Examine crystal form. Six-sided prisms with pointed terminations indicate quartz.
- Look at the color depth. Tangerine quartz color sits on the surface—look into the crystal and see colorless interior, especially at fractures.
- Rub/scratch the surface. The thin iron film can rub off or scratch, revealing clear quartz; the orange does not pervade the crystal.
- Hardness. Quartz scratches glass and steel (Mohs 7); a knife will not scratch the crystal body.
- Streak. The iron coating may leave a faint rusty streak; the quartz itself streaks white.
- Check terminations and conchoidal fracture on broken faces.
Key Diagnostic Tests
- Hardness: 7; scratches glass, unscratched by knife.
- Streak: white (rusty only from the surface film).
- Cleavage/fracture: none/conchoidal.
- Acid: quartz is inert; a drop of acid may slowly dissolve some surface iron film.
- Density: ~2.65.
Common Look-Alikes
- Citrine: orange color is internal and even, not a surface film; citrine looks transparent yellow-orange throughout, while tangerine quartz is clear inside with an orange skin.
- Hematite-included (ferruginous) quartz / harlequin quartz: iron is internal as red flecks rather than a surface coat.
- Carnelian: massive, no crystal faces, waxy—not a faceted hexagonal crystal.
- Dyed/coated quartz (e.g., aura quartz): treated coatings give metallic or unnaturally even iridescent color; natural tangerine staining is uneven and rusty.
Where It Is Found
The best-known tangerine quartz comes from Brazil (Minas Gerais), where iron-rich groundwater stains quartz points. Iron-coated quartz also turns up in many quartz-vein and pegmatite districts worldwide wherever weathering iron oxides bathe crystals.
Frequently asked questions
How can you tell if tangerine quartz is real?
Genuine tangerine quartz has its orange color as a surface iron-oxide film over clear or milky quartz. Look into the crystal or at a broken edge and you should see colorless quartz beneath the orange skin.
What is the difference between tangerine quartz and citrine?
Citrine is colored throughout by internal iron, appearing evenly transparent orange. Tangerine quartz is clear inside with an orange surface coating that can rub or scratch off.
Is tangerine quartz dyed?
Authentic tangerine quartz is naturally iron-stained, not dyed. Be cautious of unnaturally even or metallic-looking coatings, which indicate artificial treatment rather than natural hematite staining.
Where does tangerine quartz come from?
Most comes from Minas Gerais, Brazil, where iron-rich water stains the crystals, though iron-coated quartz occurs in many vein and pegmatite localities worldwide.
Tangerine Quartz identified by the community
Recent Tangerine Quartz specimens identified with Rock Identifier.
