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Petrology

Augen gneiss

Augen gneiss

Gneiss got its name from Erzgebirge (Germany) miners. « Gneiss » comes from the German words gneis,...

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Basalt

Basalt

During volcanic eruptions, high-temperature lava (1100-1200°C) is expelled and sometimes sprays over several...

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Chalk

Chalk

When standing at the foot of a chalk cliff, it is difficult to imagine the mechanism behind the formation of...

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Clay

Clay

In Normandy, a few metres thick grey deposit can be found at the foot of the cliffs between Le Havre and...

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Eclogite

Eclogite

Eclogite derives its name from the Greek word eklogê, which means « choice ». This metamorphic rock is an...

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Flint

Flint

The cliffs of Normandy are composed of alternating layers of chalk and flint. Flint is a very hard...

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Gabbro

Gabbro

Gabbro is named after a village in Tuscany (Italy). The colour of this volcanic rock varies from bluish grey...

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Glaucophanite

Glaucophanite

Glaucophanite is commonly known as « glaucophane schist » or « blueschist ». This high-pressure...

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Granite

Granite

Granite is a rock commonly associated with the coast of Brittany. It is a very common clear-coloured type of...

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Marble

Marble

Marble derives its name from the Greek word marmaros, which means « shining stone ».

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Obsidian

Obsidian

Also known as « obsidian glass », obsidian got its name from Roman general Obsius, who was the first to...

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Sandstone

Sandstone

Sandstone is a clastic sedimentary rock. It means is composed of fragments – or clasts – broken off other...

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Schist

Schist

Schist is a metamorphic rock with flat sheet-like grains. It contains elongated minerals arranged in roughly...

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Volcanic bomb

Volcanic bomb

A volcanic bomb is a porous and honeycomb mass of molten rock violently expelled in a viscous form. As it...

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The Museum's petrology collections

Petrology is the branch of geology which focuses on the study of the origin, composition, and structure of rocks. Rocks are naturally occurring solid aggregates of minerals. They are found almost always in solid form (find out more about the Museum's mineralogy collections).

The Museum's petrology collections help us understand the geological history of the area, but also the planet. Rocks are invaluable sources of information on how landscapes evolved and are also crucial in understanding the rock formation process.

Did you know that a stone could be soft, or could even smell ? From coccoliths to molten lava, get ready to discover what lies underneath our feet !

Cliffs, volcanoes, mountains : explore these various landscapes and what they are made from in just a few clicks !

 

Augen gneiss

Gneiss got its name from Erzgebirge (Germany) miners. « Gneiss » comes from the German words gneis, gneisig, which means « hard » and « strong ».

Basalt

During volcanic eruptions, high-temperature lava (1100-1200°C) is expelled and sometimes sprays over several thousands of square miles. Once it cools down, it solidifies (at a temperature of approximately 1000°C). In 95% of cases, lava cools into basalt rock.

Chalk

When standing at the foot of a chalk cliff, it is difficult to imagine the mechanism behind the formation of such a huge rock exposure. As incredible as it may sound, chalk cliffs result from the gradual accumulation of calcite shells from microorganisms called coccolithophores.

Clay

In Normandy, a few metres thick grey deposit can be found at the foot of the cliffs between Le Havre and Octeville-sur-mer. This deposit is called Kimmeridge Clay.

Eclogite

Eclogite derives its name from the Greek word eklogê, which means « choice ». This metamorphic rock is an unusually dense silicate rock has a massive texture. This type of rock was used during the Neolithic Age to produce polished axes.

Flint

The cliffs of Normandy are composed of alternating layers of chalk and flint. Flint is a very hard sedimentary rock which contains silica.

Gabbro

Gabbro is named after a village in Tuscany (Italy). The colour of this volcanic rock varies from bluish grey to dark grey, sometimes almost black, with greenish shades.

Glaucophanite

Glaucophanite is commonly known as « glaucophane schist » or « blueschist ». This high-pressure metamorphic rock belongs to the greenschist group.

Granite

Granite is a rock commonly associated with the coast of Brittany. It is a very common clear-coloured type of rock. It can be predominantly white, pink, or grey, depending on its mineralogy. Several white, pink, or black minerals are usually visible on its surface.

Marble

Marble derives its name from the Greek word marmaros, which means « shining stone ».

Obsidian

Also known as « obsidian glass », obsidian got its name from Roman general Obsius, who was the first to bring a sample of this stone from Ethiopia to Rome.

Sandstone

Sandstone is a clastic sedimentary rock. It means is composed of fragments – or clasts – broken off other rocks by physical weathering or erosion. Sandstone is composed mainly of sand-sized minerals or rock grains. During diagenesis, these sediments were cemented to form this rock.

Schist

Schist is a metamorphic rock with flat sheet-like grains. It contains elongated minerals arranged in roughly parallel layers. These minerals usually easily split off into flakes or slabs. Schist is classified as a metamorphic rock, which means it is formed under extreme heat and pressure, even though it usually originates from sedimentary rocks.

Volcanic bomb

A volcanic bomb is a porous and honeycomb mass of molten rock violently expelled in a viscous form. As it reaches the ground, this magma cools into solid spindle, cylindrical, or spherical-shaped fragments with cracked outer surfaces, hence the name « bread-crust bombs ».

Augen gneiss

Augen gneiss

Gneiss got its name from Erzgebirge (Germany) miners. « Gneiss » comes from the German words gneis,...

Scope note

Basalt

Basalt

During volcanic eruptions, high-temperature lava (1100-1200°C) is expelled and sometimes sprays over several...

Scope note

Chalk

Chalk

When standing at the foot of a chalk cliff, it is difficult to imagine the mechanism behind the formation of...

Scope note

Clay

Clay

In Normandy, a few metres thick grey deposit can be found at the foot of the cliffs between Le Havre and...

Scope note

Eclogite

Eclogite

Eclogite derives its name from the Greek word eklogê, which means « choice ». This metamorphic rock is an...

Scope note

Flint

Flint

The cliffs of Normandy are composed of alternating layers of chalk and flint. Flint is a very hard...

Scope note

Gabbro

Gabbro

Gabbro is named after a village in Tuscany (Italy). The colour of this volcanic rock varies from bluish grey...

Scope note

Glaucophanite

Glaucophanite

Glaucophanite is commonly known as « glaucophane schist » or « blueschist ». This high-pressure...

Scope note

Granite

Granite

Granite is a rock commonly associated with the coast of Brittany. It is a very common clear-coloured type of...

Scope note

Marble

Marble

Marble derives its name from the Greek word marmaros, which means « shining stone ».

Scope note

Obsidian

Obsidian

Also known as « obsidian glass », obsidian got its name from Roman general Obsius, who was the first to...

Scope note

Sandstone

Sandstone

Sandstone is a clastic sedimentary rock. It means is composed of fragments – or clasts – broken off other...

Scope note

Schist

Schist

Schist is a metamorphic rock with flat sheet-like grains. It contains elongated minerals arranged in roughly...

Scope note

Volcanic bomb

Volcanic bomb

A volcanic bomb is a porous and honeycomb mass of molten rock violently expelled in a viscous form. As it...

Scope note

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Free entry

How to find us ?
Muséum d'histoire naturelle
Place du Vieux Marché
76600 LE HAVRE
Phone : +33(0)2 35 41 37 28
museum@lehavre.fr

Opening hours

Open from Tuesday to Sunday :
from 10AM to noon
to 2PM to 76PM

Closed on Monday and Thursday morning

More information

The collection database

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