Rutile

Rutile is an unusual mineral which will likely be most popular with the more serious mineral collectors.

These pieces are specimens of Rutile itself – not as an inclusion into another mineral, for example Rutilated Quartz.

Appearance, Uses and History

Rutile is well known for forming needle like inclusions in other materials; especially Quartz, which is known as Rutilated Quartz.

These pieces are used as collectors specimens, or rarely, gemstones. Rutile actually cuts great faceted stones, but unfortunately the larger cuts appear opaque, which limits the size at which they can be cut.

Thin inclusions of Rutile needles are the cause of some interesting optical effects such as asterism in certain stones; including ‘star’ Sapphires.

Rutiles primary use is as an ore of Titanium, but it is also used industrially as a pigment for white paints and ceramic glazes.

Synthetic Rutile has been created, and they are sometimes used for jewellery. They are nearly colourless, with a yellow or brown tinge. They were for a time used as substitutes for Diamond!

The mineral was known as ‘red schorl’ in the past. This is likely due to its similarity to schorl when included, aka black Tourmaline. To be clear – rutile is not a form of schorl.

Locales

Rutile can be found in a range of locales worldwide as crystals or as inclusions, including parts of Armenia, Australia, Austria, Belgium, Brazil, Bulgaria, Canada, Chile, Czechia, Finland, France, Germany, Greece, Hungary, Italy, Madagascar, Mexico, Mozambique, Namibia, Norway, Pakistan, Portugal, Russia, Sierra Leone, Slovakia, Spain, Sweden, Switzerland, the UK, the USA, and Zambia.

Distinct crystals can occur too, with excellent specimens found across much of Europe and a few of the ‘usual suspects’ worldwide – Armenia, Austria, Brazil, Canada, France, Germany, Italy, Madagascar, Namibia, Pakistan, Spain, Switzerland, the USA, and Zambia.

Mineralogy

Chemistry
Titanium dioxide, with the formula TiO2.
Colours and Variations
Dark red, metallic grey, brown-red, orange-red, red-black, golden-yellow, straw-yellow.
Streak
White to light brown.
Luster
Adamantine, metallic, submetallic
Fracture
Uneven.
Transparency
Translucent to opaque.
Crystal habit
Often forms as needle like inclusions into another crystal, however, on its own it tends to form as striated prismatic crystals.
Mohs hardness
6.0 – 6.5
Specific Gravity
4.2-4.3
Fluorescence
N/A
Easiest testing method
It can be a little difficult to distinguish Rutile crystals from Cassiterite and Schorl; however, there are differences in hardness and specific gravity which can be used to distinguish. Rutile also has extremely high dispersion.
Common Treatments
Yellow synthetic Rutile can be heat treated to turn it blue.

Hazards and Warnings

Almost all rocks, minerals (and, frankly, almost all other substances on earth) can produce toxic dust when cutting, which can cause serious respiratory conditions including silicosis.

When cutting or polishing rocks, minerals, shells, etc, all work should be done wet to minimise the dust, and a suitable respirator or extraction system should be used.

Translations

Arabic:

  • الروتيل

Hindi:

  • रूटाइल

Portuguese:

  • rutilo

Bengali:

Indonesian:

Punjabi:

English:

  • rutile

Italian:

  • rutilo

Russian:

  • рутил

French:

Japanese:

  • ルチル

Spanish:

  • Rutilo

German:

  • Rutil

Korean:

  • 금홍석

Thai:

Gujurati:

Mandarin and Traditional Chinese:

  • 金紅石

Urdu:

Further Reading / External Links