Frosterley Marble is a black,

bituminous Bitumen ( , ) is an immensely viscous constituent of petroleum. Depending on its exact composition, it can be a sticky, black liquid or an apparently solid mass that behaves as a liquid over very large time scales. In American English, the m ...

coral Corals are colonial marine invertebrates within the subphylum Anthozoa of the phylum Cnidaria. They typically form compact Colony (biology), colonies of many identical individual polyp (zoology), polyps. Coral species include the important Coral ...

iferous limestone containing fossil crinoids of the Lower Carboniferous (Mississippian ), some 325 million years ago. It outcrops in Weardale,

County Durham County Durham, officially simply Durham, is a ceremonial county in North East England.UK General Acts 1997 c. 23Lieutenancies Act 1997 Schedule 1(3). From legislation.gov.uk, retrieved 6 April 2022. The county borders Northumberland and Tyne an ...

, England, including near the village of Frosterley whence it is named.

Geology

Unlike a true

marble Marble is a metamorphic rock consisting of carbonate minerals (most commonly calcite (CaCO3) or Dolomite (mineral), dolomite (CaMg(CO3)2) that have recrystallized under the influence of heat and pressure. It has a crystalline texture, and is ty ...

, it is not a

metamorphic rock Metamorphic rocks arise from the transformation of existing rock to new types of rock in a process called metamorphism. The original rock ( protolith) is subjected to temperatures greater than and, often, elevated pressure of or more, caus ...

, but is so-called because it can take a fine polish. Concentrations of such corals as '' Dibunophyllum bipartitum'' and of

brachiopod Brachiopods (), phylum (biology), phylum Brachiopoda, are a phylum of animals that have hard "valves" (shells) on the upper and lower surfaces, unlike the left and right arrangement in bivalve molluscs. Brachiopod valves are hinged at the rear e ...

remains contribute to its attractiveness when sections are polished.

Use

It is cut and polished for use as ornate stone, and was much desired for church decoration, particularly during the Middle Ages. The decorative columns found in

Durham Cathedral Durham Cathedral, formally the , is a Church of England cathedral in the city of Durham, England. The cathedral is the seat of the bishop of Durham and is the Mother Church#Cathedral, mother church of the diocese of Durham. It also contains the ...

date from about 1350. It has been used as far afield as India, as the base of the pulpit in St. Thomas Cathedral, Mumbai.

References

External links

Stone in Archaeology database
{{UK-geology-stub Geology Limestone Geology of County Durham Carboniferous geology Sculpture materials Stone (material)

Geology

Use

See also

References

External links