Raudonoji tigro akis - www.Kristalai.eu

Red tiger's eye

Red tiger's eye • "Bull's eye" / "Ox's eye" Species: Quartz (SiO₂) with oriented fibrous structure (cat's eye effect / chatoyancy) Color origin: oxidation rich in hematite • often enhanced by gentle heating Hardness ~6.5–7 • SG ~2.64 • Luster: from silky to vitreous

Red tiger's eye — a silky gleam in chestnut shades

Red tiger's eye – the "cousin" of tiger's eye in warm, mahogany tones. It retains the classic cat's eye play – light glides as a bright band across the surface – and deepens the palette from honey to cinnamon, brick, and wine. Tilt it once – and the single, shining "eye" winks; tilt it again – and it seems the stone is winking at you. (Rocks don't flirt, but this one definitely tries.)

🐅
Family
Tiger's eye quartz (golden) → red variant ("bull's/ox's eye")
Feature
Cat's eye effect from parallel fibrous bands preserved in quartz
🌡️
Color note
Natural red occurs; most material is gently heated to intensify the reds

Identity and formation 🔎

Quartz with preserved "fiber memory"

Tiger's eye starts as crocidolite (blue fibrous amphibole). Over time, silica replaces the fibers with microcrystalline quartz (pseudomorphosis), but preserves their parallel arrangement. These preserved "silk" bands concentrate light into a bright line – this is the cat's eye effect.

Where does the red come from?

Iron oxidizes in and around the fibers. The transition goethite → hematite shifts the palette from golden browns toward reds and mahogany tones. Many red stones on the market are gently heat-treated to enhance this reaction; it remains quartz all along.

Title tip: Red tiger's eye is often called "bull's eye" or "ox's eye". The golden variant is simply tiger's eye, and the blue precursor is falcon's eye.

Color and pattern glossary 🎨

Palette

  • Dark chestnut — hematite-rich zones with a bright "eye."
  • Brick red — classic warm tone.
  • Rusty/cinnamon brown — transitional areas toward golden bands.
  • Honey/amber — remaining golden tiger's eye veins.
  • Dark "ink" lines — fine iron oxide overlays that increase contrast.

Stones often show layered bands, where red and golden colors alternate – they look great in large cabochons and beads.

Pattern terms

  • Cat's eye band — a bright line sliding as the lighting angle changes.
  • Banded chatoyancy — several parallel bands create a broader "glow."
  • Hematoid wash — diffuse redness when hematite is very fine.
  • Tiger iron interlayers — if alternating with red jasper/hematite (see "cousins").

Photography tip: One small light source at ~30° angle makes the "eye" move. Keep the light fixed and tilt the stone – the band will "chase" you like a curious cat.


Physical properties 🧪

Property Typical range / Note
Composition SiO₂ (microcrystalline quartz) with iron oxides along preserved fibrous bands
Structure Pseudomorph after crocidolite; parallel fibrous texture → cat's eye effect
Hardness ~6.5–7 (durable; edges may chip from sharp impact)
Relative density (SG) ~2.60–2.66
Luster Silky on banded surfaces; glassy on polished
Transparency Opaque, on thin edges – slightly translucent
Treatments Common: heating to enhance redness; sometimes: dyeing (look for overly uniform "neon" red)
Cutting geometry: The cat's eye band is strongest when fibrous bands run parallel to the cabochon's long axis, so the bright line is over the dome's top.

Under the magnifier 🔬

"Silk," not cracks

At 10× you will see fine, parallel bands or fibers – straight and consistent. Real cracks meander or branch; fibers "stick to their band."

Signs of hematite

In redder zones – fine, opaque dots/films along the bands. In strong light, they look like a velvety haze rather than sparkling dots.

Orientation test

Turn the cabochon: the cat's eye line should glide smoothly. If it breaks or "stops," the cut crossed the bands at an angle.


Similar materials and how to distinguish them 🕵️

Red jasper

Similar color but without cat's eye effect. Jasper has a grainy/rough texture; no “eye” appears.

Tiger iron

Natural formation: tiger eye + hematite + red jasper with bright, metallic bands. Heavier, with steel-gray bands reflecting like metal.

Pietersite

Cracked and recemented tiger/falcon eye → swirling chatoyancy instead of straight bands. Looks like a stormy moving sky mosaic.

“Cat's eye” fiber optic glass

Uniform, “neon” colors with a very sharp, perfectly centered band that barely changes when tilted; softer and without natural banding.

Dyed agate

May be red and shiny but does not show a moving cat's eye band. Bands follow agate patterns, not straight “silky” lines.

Quick checklist

  • Does a single bright band shift when changing the angle?
  • Are fine parallel fibers visible at 10× magnification?
  • Is the color natural (rust/mahogany), not uniform “neon” (often dyed)?

Locations 📍

Classic localities

North Cape, South Africa – the historic heart of tiger eye deposits; the red material often comes from the same bands. Also Namibia and Western Australia (where “tiger iron” is found).

Elsewhere

Tiger eye textured quartz is also mined in Brazil, India, and elsewhere. Red can be natural or heat-treated – depending on the batch.


Care and processing notes 🧼💎

Daily care

  • Quartz hardness is good, but protect from sharp impacts (edges may chip).
  • Clean with lukewarm water and mild soap using a soft cloth; rinse and dry.
  • Avoid prolonged high temperatures; extreme heat can dull color or cause stress.

Use in jewelry making

  • Suitable for cabochons, beads, and inlays. For rings/bracelets, choose protective bezels.
  • If glued, avoid hot ultrasonic/steam cleaners to preserve the setting.

Processing (lapidary work)

  • Orient the plates so fibers run parallel to the cabochon's length – the effect is strongest.
  • Work cool; before the final cerium oxide or other polishing step, carefully pre-polish (up to 3k–8k).
  • Slightly ground the edges (bevel) to protect the "silk" at the surface.
Transparency of treatments: Red tones are often enhanced by heating; natural reds exist but are rarer. Clear labeling helps maintain collection integrity and interest.

Practical demonstrations 🔍

"Catch the eye"

Direct a small spotlight at the cabochon and slowly tilt it. A bright cat's eye band should glide across the dome like a performer followed by a spotlight.

Fiber search

With a 10× loupe, look for straight, parallel "silks". If the "lines" meander like rivers, you might have a pietersite swirling mosaic.

A little joke: red tiger's eye — because sometimes a cat's eye appears in a velvet tuxedo.

Questions ❓

Is red tiger's eye natural?
Yes — red shades naturally occur due to iron oxidation, but the brightest material on the market is often heated to deepen the hematite red.

Will the color fade?
Stable when kept indoors. Avoid prolonged high temperatures or harsh chemicals; normal sunlight and wear are fine.

How does it differ from "tiger iron"?
Red tiger's eye – a uniform stone (quartz) with a cat's eye effect. Tiger iron – a banded combination of tiger's eye, red jasper, and hematite – more "metallic," heavier, and boldly striped.

Can it be dyed?
Sometimes. Too uniform, saturated cherry tones may indicate dyeing. Natural/heated reds show subtle variation along the bands.

Which cut best reveals the effect?
A raised cabochon when the fibers run lengthwise – then a bright band will lie across the top and slide when tilted.

Return to the blog