Is Red Obsidian Rare? A Geologist‘s In-Depth Guide to this Fascinating Volcanic Glass

In short – yes, genuine natural red obsidian is exceptionally rare. While vibrant ruby-red obsidian can be purchased, this striking color is artificially induced rather than found in nature. True red obsidian simply does not exist geologically. Let‘s take a deep dive into the origins, properties, colors, and rarity of this stunning volcanic glass to uncover the facts and myths around red obsidian.

Obsidian is a silica-rich natural glass formed from lava cooling rapidly on or near the earth‘s surface. Its chemical composition and amorphous structure make obsidian a mineraloid rather than a true mineral. Along with its smooth glassy texture, obsidian‘s claim to fame is its conchoidal fracturing pattern that produces incredibly sharp edges – our ancestors even used it to make knives, arrows, and spears!

While typically jet black, obsidian also forms in various dark green, brown, blue, red, orange, and yellow hues due to mineral inclusions and oxidization. But vibrant red obsidian only enters the picture through modern artificial treatment. So let‘s explore how natural obsidian gets its color, where genuine reddish obsidian can actually be found, and why true red obsidian is so impossibly rare.

What Gives Obsidian Its Color?

Obsidian‘s color stems from its chemical makeup and inclusions formed when the original lava cooled into glass.

Black obsidian makes up about 80% of deposits worldwide. Its dark color comes from a high concentration of iron and magnesium. Fine grained black obsidian is sometimes used as a gemstone.

Green obsidian gets its olive to forest green shades from the presence of the mineral fayalite. This iron-rich olivine mineral is typically formed in lava that is iron-rich and silica-poor.

Brown obsidian, including the coveted "mahogany" type, gets its rich reddish-brown hue from iron oxides in the lava. Hematite and magnetite inclusions tint the glass.

Blue obsidian is extremely rare. The striking cobalt blue color comes from inclusions of tiny needle-like crystals of ilmenite.

Yellow or orange obsidian forms when sulfur combines with iron in the lava, producing iron sulfides. Sulfur also contributes to silica polymers that influence obsidian‘s viscosity.

Red obsidian‘s vibrant ruby color is due to tiny disseminated crystals and particles of iron oxide minerals like hematite, magnetite, or limonite. But is this red color actually found in nature? Let‘s explore that next.

Does Natural Red Obsidian Exist?

According to expert geologists and gemologists, vibrant ruby-red obsidian does not occur naturally. No deposit of crimson red obsidian has ever been discovered. While obsidian takes on many hues from black to brown, green, and orange, a true rich red is impossible to produce geologically.

Natural obsidian with a reddish color exists but is limited to darker earthy tones of red-brown, rust, maroon, or blood-red caused by iron oxide inclusions. Bright ruby red obsidian only enters the picture through modern treatment.

Various methods are used commercially to produce synthetic red obsidian:

• Heating powdered hematite or other iron oxides into already-formed obsidian
• Injecting red dye into fractures and cavities
• Coating the surface with red pigments or metal oxides

So while stunning red obsidian stones and jewelry can be purchased, they are altered from their natural state. Where can you actually find obsidian with reddish hues in nature? Let‘s look at a few sources.

Natural Sources of Reddish Obsidian

While true crimson red obsidian is synthetic, various volcanic glasses with earthy red to brown colors have been found naturally in a handful of places around the world:

Mahogany Obsidian

This natural obsidian has cloudy swirls and patterns in shades of reddish-brown. It forms from iron oxide crystallites of hematite/magnetite dispersed through the volcanic glass. Well-known sources include Glass Buttes, Oregon and Armenia‘s Mt. Ararat where it was used since 5000 BC for tools.

Red Sheen Obsidian

A very rare obsidian with streaks of hematite crystallization reflecting reddish and rainbow sheens. It is found exclusively in the Black Rock Desert volcanic field in southwestern Utah. Native Americans used it for projectile points and ceremonial objects.

Pele‘s Blood

Not true obsidian, this is natural volcanic glass from Hawaii formed by lava fountains, not flows. It has an opaque red color and Sandy texture from shattered lava droplets fused by rapid heat and cooling cycles.

Apache Tears

Small round nodules of black or smoky gray obsidian found in Arizona and Nevada. When held to light, they reveal concentric banding and a tiny hint of red due to iron inclusions.

Rainbow Obsidian

Natural rainbow sheen obsidians from Mexico and Indonesia sometimes exhibit reddish iridescent flashes among the colorful bands. This occurs when light hits hematite micro-inclusions.

While not pure red, these rare obsidians represent some of the few natural instances of red hues occurring in volcanic glass worldwide. But what makes true red obsidian so impossible to produce geologically? Let‘s explore why it‘s so rare.

What Makes Red Obsidian So Rare?

For obsidian to form with a vivid ruby red color naturally would require a precise and unlikely combination of conditions:

• High iron lava composition: Iron oxide minerals like hematite provide the red color. But most obsidian flows are lower in iron which produces black glass instead.

• Rapid cooling environment: Obsidian‘s glassy texture comes from fast cooling. Slower cooling promotes crystallization rather than glass formation, even from iron-rich lava.

• Low viscosity lava: Color-carrying iron oxides need to mix thoroughly into the melt. Highly viscous lava prevents even dispersal of crystals.

• Absence of other minerals: Other elements like manganese can react with iron to form different minerals that alter the final glass color.

• Transparency: Fully transparent glass allows the eye to perceive the vivid red color. Opaque or cloudy glass appears darker.

• Pristine conditions: Any weathering or hydration after formation will degrade obsidian‘s glass structure and original color over time.

With so many specific requirements, Mother Nature has yet to produce a perfect storm that results in natural red obsidian – and she may never! But while elusive in nature, there are plenty of incredible obsidians to discover.

Natural Obsidian Oddities & Wonders

While vibrant red obsidian is scientifically impossible, obsidians exhibiting other rare colors, optical effects, and patterns exist in Nature and are highly valued:

• Rainbow obsidian: Displays an iridescent rainbow sheen across its surface when polished.

• Silver Sheen: Exhibits a flashy silver iridescence. Rarest variety found near Lake Kastoria, Greece.

• Gold Sheen: Rare golden metallic sheen obsidian from Greece and Mexico.

• Fire obsidian: Extremely rare and desirable. Reflects rainbow colors against a black background.

• Snowflake obsidian: Black with white "snowflake" crystal shapes. Delicate and challenging to cut.

• Obsidian straw: Rare elongated tubular formations of glassy lava.

• Mahogany obsidian: Natural red-brown swirls from iron inclusions.

• Peacock obsidian: Vibrant blues, greens and orange metallic sheen. Very rare.

• Galaxy obsidian: Glittery inclusions folded and stretched into streaks resembling a night sky.

The quest for these natural obsidian oddities brings excitement to collectors like myself. While artificial red obsidian has visual appeal, I prefer the thrill of sourcing authentic unusual types created by earth‘s forces alone. That connection to nature brings true satisfaction.

How Much Does Red Obsidian Cost?

Since red obsidian is artificially colored, it has a lower value than rare natural types. Here are price ranges for obsidian by color and quality:

For reference, natural mahogany obsidian sells for approx. $50-300 per kilogram. Facet grade natural black obsidian costs $50-100 per carat.

However, artificially colored obsidians may sometimes be sold as enhanced natural material. Reputable dealers will disclose any treatments. Scrutinize red obsidian priced significantly above $50/lb, which should raise concerns of misrepresentation.

Should You Add Red Obsidian To Your Collection?

Despite its artificial origins, man-made red obsidian remains a beautiful and budget-friendly choice for collectors. It takes a good polish and has a festive ruby red radiance when made into jewelry or tumbled stones.

However, I advise collectors to exercise caution when sourcing red obsidian. Seek reputable dealers who fully disclose any enhancements. For completely natural specimens, consider alternative red-hued obsidians like mahogany or apache tears.

Or take the path less traveled and search for one of the many other wondrous obsidian oddities created uniquely by natural forces. There‘s more beauty and intrigue to be found in nature‘s true kaleidoscopic volcanic glass!