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Brookite Gemstone: Properties, Meanings, Value & More

ブルッカイトの宝石：特性、意味、価値など

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Brookite is a metallic gemstone commonly found in shades of brown like reddish-brown or yellowish-brown. The mineral is closely related to rutile and anatase.

Is brookite rare or common? Brookite as a mineral isn’t super rare, but crystals suitable for becoming gemstones are quite rare. More often, you’ll see cut gemstones of brookite in quartz.

Despite its rarity, brookite has some impressive traits as a gemstone — its colorful sparkle, or “fire,” is almost 200 percent greater than that of diamonds! Plus, it can have a submetallic or adamantine (diamond-like) luster.

Eager to learn more? Read on to find out all of brookite’s properties, prices, benefits, and history!

Image credit: Rob Lavinsky, iRocks.com – CC-BY-SA-3.0

What Is A Brookite Crystal?

Brookite is a rare semi-precious gemstone found in brown and rarely blue hues.

Other monikers for brookite are:

• Jurinite

• Pyromelane

• Acide Titanique

Astrologically, brookite is lucky for Cancer signs.

Industrially, what is brookite used for?

Brookite Uses

Brookite isn’t used commercially as much as rutile or anatase. Nevertheless, brookite does have benefits and scientists have created synthetic brookite for research into these applications.

Synthetic brookite can be used for:

• Paints

• Orthopedic implants (anti-corrosive and biocompatible coatings)

• Research into photocatalytic properties

Photocatalysis is when a material can absorb photons after being exposed to light underwater, exciting its own electrons and causing the electrons to split the water into hydrogen and oxygen. This property has important uses like cleaning oil spills, disinfecting water, and purifying air.

Minerals like brookite can be processed for the many applications of titanium dioxide, like:

• Pigment – Often in paints, toothpastes, and foods

• Thin-Film Deposition – Reflective coating for dielectric mirrors or decorative gems like mystic topaz

• Sunscreen – Strong UV-light absorption & resistance to discoloration under UV-light; Often combined with zinc oxide

• Ceramic Glazes – Makes it opaque and aids crystallization during cooling

• Cosmetics – Oil and water dispersible

Shifting back to brookite, it’s time to go over its mineral properties.

Pictured above: Interpenetrating twinned brookite crystal with doubly-terminated quartz on one side | Image credit: Rob Lavinsky, iRocks.com – CC-BY-SA-3.0

Brookite Specifications & Characteristics

As one of the three — or four, depending on who you ask — mineral forms of titanium dioxide, brookite’s formula is TiO2. The other two are rutile and anatase, which we’ll compare to brookite in the next section. A possible fourth is the monoclinic akaogiite.

Common impurities in brookite minerals include iron, tantalum, and niobium.

Brookite only forms crystals but in various shapes: tabular, prismatic, pyramidal, and pseudo-hexagonal. Many are elongated with longitudinal striations.

Some notable properties include brookite’s extremely high refractive index (over-the-limit on a refractometer) and dispersion — both higher than diamond.

Brookite properties listed:

• Mohs hardness: 5.5-6

• Color: Brown, deep red, reddish-brown, yellowish-brown, black, rarely blue; Hourglass-shaped color zoning possible in blue crystals

• Crystal structure: Orthorhombic

• Luster: Submetallic, sub-vitreous, vitreous, sub-adamantine, adamantine

• Transparency: Transparent to opaque

• Refractive index: 2.583-2.740

• Density: 4.08-4.18

• Cleavage: Indistinct/poor on {120}, in traces on {001}

• Fracture: Subconchoidal or irregular/uneven

• Streak: White, grayish-white, or yellowish-white

• Luminescence: None

• Pleochroism: Present; Very weak to strong in yellowish-brown to reddish-brown to orange or golden-brown

• Birefringence: 0.117-0.157

• Dispersion: 0.131 (very strong)

Pictured above: Quartz crystal with silvery rutile needles and red brookite blades | Image credit: Rob Lavinsky, iRocks.com – CC-BY-SA-3.0

Difference Between Anatase, Rutile, and Brookite

Now let’s see how brookite properties compare to anatase and rutile:

• Rarity: Anatase - Rarest; Brookite - Rare; Rutile - Most Common (including for gems)

• Crystal System: Brookite - Orthorhombic; Rutile & Anatase - Tetragonal

• Optic Character: Brookite - Biaxial; Rutile - Uniaxial (usually); Anatase - Biaxial or Uniaxial

• Hardness: Brookite & Anatase - 5.5 to 6; Rutile - 6 to 6.5

• Dispersion: Brookite Lowest - 0.131; Anatase Higher - 0.214 (0), 0.259 (e); Rutile Highest - 0.280-0.330

• Density: Anatase - 3.79-3.97; Brookite - 4.08-4.18; Rutile - 4.20-4.30 (tantalum-bearing up to 5.60)

• Birefringence: Anatase - 0.046-0.073; Brookite - 0.117-0.157; Rutile - 0.287

Pictured above: Arkansite variety of brookite | Image credit: Ra’ike, CC-BY-SA-3.0

Types of Brookite

The important types of brookite to know are:

Arkansite

Arkansite is a black, opaque variety of brookite named for its discovery in Arkansas, USA. The lustrous black appearance of these sharp, bipyramidal crystals comes from iron and niobium substituting for titanium.

This brookite variety has also been found in Siberia, Russia.

Platinum Quartz

“Platinum quartz,” or sometimes “dragonflies in quartz,” is more of a trade name than a variety. It refers to quartz crystals (mostly from Brazil) containing inclusions of brookite blades and needle-like rutile that resemble insects.

This stone differs from “platinum aura quartz,” a diffusion-treated quartz stone similar to mystic quartz. (Note: Neither contains platinum).

Speaking of mystic phenomena, let’s look at brookite’s metaphysical properties next.

Brookite Meaning & History

Metaphysically, brookite symbolizes spiritual ascension, higher realms, and new beginnings. Some associate brookite crystals with the mantra “this too shall pass,” representing the inherent but often relieving fact that nothing in life is permanent.

History

Brookite was first discovered in Wales, UK, around 1809. The brookite crystals from this type locality were transparent to translucent, red to brown, and bladed with long striations.

French mineralogist Armand Lévy named the mineral “brookite” in 1825 to honor English textile trader and crystallographer Henry James Brooke.

Brooke’s contributions to the field include discovering 12 minerals, which include arfvedsonite, thomsonite, and annabergite, along with co-authoring Elementary Introduction to Mineralogy in 1852.

Though some of the finest brookite crystals have been found in Snowdonia (Wales), arguably even better specimens emerged in the late 1900s in the Alps of France and Switzerland. Pakistan deposits appeared in 2004, producing some of the best specimens since.

American mineralogist Charles Upham Shepard discovered arkansite in 1846. Shepard thought it was a new mineral, but Welsh mineralogist William Hallowes Miller reported in 1849 that arkansite was identical to brookite.

Nevertheless, A.A. Konev, E.I. Vorobyev, and K.A. Lazebnik discovered more arkansite specimens in Russia in 1996.

Pictured above: Quartz crystal with brookite inclusions | Image credit: Rob Lavinsky, iRocks.com – CC-BY-SA-3.0

Brookite Healing Properties

As a predominantly brown healing stone, brookite possesses the grounding, balancing, and stabilizing properties inherent to brown gemstones. In energy healing, brookite crystals are great root chakra stones.

What is brookite good for physically?

Physical Healing

Physically, brookite is said to help with issues related to:

• Vision

• Balancing cerebral hemispheres of the brain

• Circulation

• Low energy

• Infertility

• Electromagnetic radiation

Emotional Healing

Emotionally, brookite crystal benefits those struggling to focus or move on. It can help you be present in the moment and handle difficult changes in life.

Image credit: Rob Lavinsky, iRocks.com – CC-BY-SA-3.0

Brookite Gemstone Properties

Besides rarity, brookite gemstone value depends on color, cut, transparency, and carat weight.

Color

Brown hues are more common in brookite, so rare blue coloring can be quite valuable. Brighter colors (such as deep garnet-like reds) can fetch higher prices, as most brookites are very dark, masking their dispersion.

Cut

Since most brookite crystals aren’t cuttable, faceted stones are rare and valuable, especially if the strong dispersion and luster are optimized.

Brookite can be cut as cabochons, but you’re more likely to find brookite in quartz gemstones. Many brookite crystals are sold uncut.

Transparency

Brookite crystals are usually only transparent in small fragments, and dark colors can make them appear opaque. Higher transparency will lend higher value.

As an inclusion in quartz, brookite can increase a quartz’s value, especially in transparent quartzes with intertwined brookite inclusions.

Carat Weight

Not only is transparency rare, but transparent brookites are always under 1-2 carats. Larger brookite stones are opaque.

Pictured above: Brookite with quartz specimen

Brookite Formation & Sources

Brookite forms as an accessory mineral in alpine veins of gneiss and schists rocks. It also forms in hydrothermal veins, contact metamorphic zones, and sometimes igneous rocks. It’s commonly found as detritus, meaning it broke off its parent rock due to weathering.

Brookite is often entirely encased by quartz. It can also grow together with rutile, but brookite will revert to a rutile structure when heated above around 750°C.

Mining Locations

Where is brookite found in the world? The top sources for gem-quality brookites are Arkansas (USA), Switzerland, and Pakistan.

Other significant sources include:

• Brazil

• France

• Russia

• Spain

• UK (England & Wales)

• USA (California, Maine, Massachusetts, New York, North Carolina)

Pictured above: Tabular brookite crystal | Image credit: Amgueddfa Cymru, Flickr, CC-BY-SA-2.0

Brookite Price & Value

Faceted brookite gemstones range from around $20 to $450 per carat. Quartz stones with brookite inclusions are around $10 per carat when faceted.

Brookite in quartz cabochons are even more affordable, typically around $3 per carat.

Crystal specimens can range more broadly. Quartz crystals with brookite inclusions start around $10 and can reach $1,850. Deep red brookite crystals are generally priciest, ranging from $17 to $3,000.

Brookite Care and Maintenance

Before we wrap up, you’ll want to know proper gemstone care.

While brookites have greater wearability than anatase or rutile, they still have mid-range hardness. If you want to sport brookite every day, we recommend a brookite in quartz bracelet or brookite jewelry with protective settings.

Clean brookite stones with mild soap, warm water, and soft toothbrush. Don’t use mechanical systems like steam or ultrasonic cleaners.

Store the stone separately from other gems to avoid scratches.

Pictured above: Three brookite blades with hourglass-like interior zoning on matrix with clear quartz| Image credit: Rob Lavinsky, iRocks.com – CC-BY-SA-3.0

Hooked on Brookite Crystals?

Brookite gemstones may be rare, but there are plenty of gorgeous pieces at affordable prices. Plus, faceted brookite is a must-have for any collection.

If you’re worried about wearability or simply finding brookite jewelry you like, you can always opt for some gorgeous quartz with brookite inclusions!

Buy brookite gemstones today!