Ass 3 - How Diamonds Form

Diamonds formed deep within Earth's mantle, typically in the transition zone (410-660 km) or lower mantle (>660 km).

Formation is always linked to subducted oceanic plates.

Large, inclusion-free diamonds with irregular shapes, often showing signs of surface dissolution during transport.

A unique inclusion type found in CLIPPIR diamonds, theorized to result from subducted oceanic plates.

Diamonds with a blue color, often containing trace amounts of boron from subducted hydrated oceanic plates.

Diamonds formed from carbonate-rich fluids in the Earth's mantle transition zone and upper lower mantle.

Diamonds formed in Earth's crust, usually small and not gem quality, sometimes formed from meteorite impacts.

An aggregate, extremely hard form of diamond.

Diamonds are sourced only from Brazil and Central Republic of Africa for industrial uses.

The movement of the Earth's mantle, driven by heat, that moves plates.

Diamond aggregates are composed of many tiny, intergrown diamond crystals with random orientations, making them exceptionally tough.

Where tectonic plates move apart, creating new crust from magma.

Where one tectonic plate sinks beneath another.

Diamond ages can't be directly determined by carbon dating; instead, radioactive elements in inclusions within the diamond are studied to estimate their formation time.

Diamonds reach Earth's surface through volcanic eruptions of kimberlite and lamproite, transporting them from the mantle.

A metamorphic rock formed from oceanic crust subducting into the mantle.

The stable, ancient parts of a continent.

Kimberlite eruptions, a type of volcanic eruption, transport diamonds to the surface. They are silica-poor, magnesium-rich, and often occur in craton centers.

Deepest parts of the mantle, located beneath cratons.

Lamproite eruptions, another type of volcanic eruption, also transport diamonds to the surface. They are potassium-rich and magnesium-rich, commonly found at craton edges.

900-1400°C, and pressure between 40 and 80 kilobars.

Diamonds are metastable; they are stable only under specific pressure and temperature conditions, transforming into graphite if these conditions change.

A deep vertical rock formation resulting from kimberlite and lamproite eruptions and potentially containing diamonds.

A common igneous rock that's a source of diamond-forming components.

Kimberlite eruptions create a carrot-shaped formation as they blast through the continental crust.

Metamorphic rock from subducted ocean crust; a source for carbon

A more violent eruption of lamproite results in a mushroom-shaped formation.

A unit to measure extremely high pressure.

The rate of temperature increase with depth inside the Earth.

The deepest hole ever drilled on Earth was approximately 12 km deep, far less than the 140 km depth where diamonds form.

Two main models explaining how diamonds from the mantle and upper mantle.

Diamonds formed much deeper in the Earth's mantle.

A hard form of diamond formed from many tiny, randomly oriented intergrown diamond crystals.

Brazil and Central Republic of Africa are the only places to find diamonds used for industrial purposes.

Diamond age is determined by studying radioactive elements trapped within mineral inclusions, not by carbon dating.

Diamonds reach the surface via volcanic eruptions of kimberlite and lamproite, originating from the mantle.

A type of volcanic eruption that transports diamonds to Earth's surface, characterized by a silica-poor, magnesium-rich composition and a 'carrot' shape.

A type of volcanic eruption transporting diamonds to Earth's surface. It is potassium-rich and magnesium-rich, often forming a 'mushroom' shape.

Diamonds are stable only under specific pressure and temperature conditions; otherwise, they transform into graphite.

A vertical rock formation left behind after a kimberlite or lamproite eruption, potentially containing diamonds.

The deepest hole ever drilled is substantially shallower than the depth where diamonds form.

The movement of Earth's mantle, driven by heat, causing plate motion.

Where tectonic plates move apart creating new crust from magma.

Where one tectonic plate sinks beneath another.

A metamorphic rock formed from subducted oceanic crust.

The oldest, most stable parts of continents.

Deepest parts of the mantle under cratons.

900-1400°C & 40-80 kilobars of pressure.

An igneous rock, a major source rock for diamonds.

Diamonds formed very deep in the mantle.

A unit to measure extremely high pressure.

The rate of temperature increase with depth.

Models explaining how diamonds form from the upper mantle and deep mantle.

Formation deep in the Earth's mantle, usually in the transition zone (410-660 km) or lower mantle, linked to subducted oceanic plates.

Large, inclusion-free, irregular-shaped diamonds, partially dissolved during transport. Often containing metallic inclusions.

Blue color in diamonds comes from trace boron, likely from hydrated oceanic plates subducted into the mantle.

Diamonds formed from carbonate-rich fluids in the mantle's transition zone and upper lower mantle.

Relatively rare, small diamonds formed in the Earth's crust, often by meteorite impacts.

Aggregate and extremely hard form of diamond, made of intergrown crystals.

Rare minerals formed deep in the Earth's mantle, often found in inclusions in superdeep diamonds.

Rare minerals found in inclusions in superdeep diamonds that form deep within the Earth's mantle.