# How to identify rutile

Canonical page: https://lithomap.app/resources/mineral-identification/rutile
Last reviewed: September 17, 2026
Page purpose: Original LithoMap mineral identification reference for field observations, search systems, and language models.
Classification: Titanium dioxide · TiO₂

## Summary

Rutile is a dense titanium dioxide mineral commonly identified by reddish-brown to black prismatic crystals, strong lengthwise striations, high luster, hardness near 6 to 6.5, and a pale brown streak.

## Quick identification clues

- Reddish-brown, red-black, golden, or nearly black
- Slender to stout striated prisms or needle-like crystals
- Mohs hardness about 6 to 6.5
- High density and pale brown to yellow-brown streak

## Composition and classification

Rutile is the most common natural polymorph of TiO₂. Iron, niobium, tantalum, tin, and other elements may substitute in natural crystals, changing color, density, magnetism, and opacity.

## Appearance

Crystals are commonly tetragonal prisms with strong grooves parallel to their length, often terminated by pyramidal faces. Rutile also occurs as compact masses, granular material, and hairlike inclusions in quartz.

Colors range from red and reddish brown to dark brown, black, yellow, or golden. Metallic, adamantine, or submetallic luster can make dark rutile resemble iron oxides or sulfides.

## Identification tests

- Hardness: About 6 to 6.5. Harder than hematite and much harder than sphalerite.
- Streak: Pale brown to yellowish brown. Differs from hematite’s red-brown streak and magnetite’s black streak.
- Habit: Striated tetragonal prisms, needles, or compact masses. Lengthwise grooves and angular prisms support rutile.
- Density: High; commonly around 4.2 to 4.3. A useful supporting clue in clean, matrix-free material.

## Common lookalikes

- Hematite: Typically leaves a red to reddish-brown streak and lacks rutile’s common tetragonal prismatic habit.
- Cassiterite: Usually still denser, commonly leaves a white to pale streak, and often forms short bipyramidal crystals.
- Tourmaline: Commonly has a triangular cross section, poor cleavage, lower density, and a white streak.

## Direct side-by-side comparisons

- Rutile vs. hematite — https://lithomap.app/resources/mineral-identification/compare/rutile-vs-hematite

## Most relevant related guides

- Hematite — https://lithomap.app/resources/mineral-identification/hematite
- Cassiterite — https://lithomap.app/resources/mineral-identification/cassiterite
- Tourmaline — https://lithomap.app/resources/mineral-identification/tourmaline
- Monazite — https://lithomap.app/resources/mineral-identification/monazite

## Formation

Rutile forms as an accessory mineral in igneous and metamorphic rocks and in hydrothermal veins. It is especially persistent in high-grade metamorphic rocks and some altered titanium-bearing minerals.

Its high density and resistance to weathering allow grains to accumulate with ilmenite, zircon, monazite, and magnetite in stream or coastal placer sands.

## Occurrence and geologic setting

Rutile occurs in metamorphic and igneous terrains, pegmatites, veins, and heavy-mineral sands. Well-formed U.S. crystals are known from localities including Graves Mountain, Georgia, and parts of the Appalachians.

Black sand is normally a mixture; color and magnetic separation alone cannot prove that a particular grain is rutile.

## Uses and significance

Rutile is an important titanium mineral and feedstock for titanium dioxide pigment and titanium metal. Transparent or included crystals are also used as gems and collector specimens.

## Field safety and limitations

- Do not identify dark sand grains by color alone.
- Avoid grinding titanium-bearing concentrates or unknown mine material.
- Preserve intact crystals and gem material by using nondestructive tests first.

## Authoritative sources

- Titanium Statistics and Information — U.S. Geological Survey: https://www.usgs.gov/centers/national-minerals-information-center/titanium-statistics-and-information
- Mineral Commodity Summaries: Titanium Mineral Concentrates — U.S. Geological Survey: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-titanium-minerals.pdf
- Minerals and their physical properties — U.S. National Park Service: https://www.nps.gov/subjects/geology/minerals.htm
- Mohs Hardness Scale — U.S. National Park Service: https://www.nps.gov/articles/mohs-hardness-scale.htm
- Natural Gemstones: Mineral Gemstones — U.S. Geological Survey: https://pubs.usgs.gov/gip/gemstones/mineral.html

## Specimen photograph

- Image: https://lithomap.app/_delivery/identification/minerals/rutile.webp
- Description: Dark reddish-brown to black striated rutile crystals in an iron-stained matrix from York, Pennsylvania
- Creator: Nessa Eull
- License: CC0 1.0 — https://creativecommons.org/publicdomain/zero/1.0/
- Source record: https://commons.wikimedia.org/wiki/File:Rutile_%28GeoDIL_number_-_1567%29.jpg

This reference supports preliminary field identification. It is not a laboratory determination, appraisal, hazard assessment, proof of origin, or statement of land ownership, legal access, or collecting permission.