Encrinite

Encrinite, from Ancient Greek (en, "in") + (krinon, "lily") are sedimentary rocks with crinoidal ossicles in excess of 50 percent of the bulk of the rock. It could be either a crinoidal packstone or crinoidal grainstone (Dunham) or a crinoidal biomicrite, crinoidal biosparite, crinoidal biomicrudite, or crinoidal biosparudite (Folk). In the first known reference to crinoids, Agricola (1546) used "Encrinos" to distinguish isolated pentagonal crinoid columnals.

As described by Miller in his work on the crinoids, the animals of this family are furnished "with a round, oval, or angular column composed of numerous articulating joints, supporting at its summit a series of plates or joints, which form a cup-like body containing the viscera, from whose upper rim proceed five articulated arms, dividing into tentaculated fingers more or less numerous surrounding the aperture of the mouth".

Fossil and Modern Crinoids

Crinoids fragments in an Encrinite. From Mark A. Wilson (Department of Geology, The College of Wooster).

Bibliography

• E. WM. Heinrich (1956): Microscopic Petrografy. Mcgraw-hill book company,inc
• M. J. Hibbard (1994): Petrography to Petrogenesis. Prentice Hall editore

Photo
Crinoids fragments in an Encrinite. PPL image, 2x (Field of view = 7mm)	Crinoids fragments in an Encrinite. PPL image, 2x (Field of view = 7mm)	Crinoids fragments in an Encrinite. XPL image, 2x (Field of view = 7mm)
Crinoids fragments in an Encrinite. PPL image, 2x (Field of view = 7mm)	Crinoids fragments in an Encrinite. PPL image, 2x (Field of view = 7mm)	Crinoid Column composed of numerous articulating joints. PPL image, 2x (Field of view = 7mm)
Piece of Crinoid Column. PPL image, 2x (Field of view = 7mm)	Crinoids fragments in an Encrinite. PPL image, 2x (Field of view = 7mm)	Crinoids fragments in an Encrinite. XPL image, 2x (Field of view = 7mm)
Crinoids fragments in an Encrinite. PPL image, 2x (Field of view = 7mm)	Crinoids fragments in an Encrinite. PPL image, 2x (Field of view = 7mm)	Crinoids fragments in an Encrinite. XPL image, 2x (Field of view = 7mm)
Crinoids fragments in an Encrinite. PPL image, 2x (Field of view = 7mm)	Crinoids fragments in an Encrinite. PPL image, 2x (Field of view = 7mm)	Crinoids fragments in an Encrinite. PPL image, 2x (Field of view = 7mm)
Crinoids fragments in an Encrinite. XPL image, 2x (Field of view = 7mm)	Crinoids fragments in an Encrinite with green Glauconite. PPL image, 2x (Field of view = 7mm)	Crinoids fragments in an Encrinite with green Glauconite. XPL image, 2x (Field of view = 7mm)
Crinoids fragments in an Encrinite with green Glauconite. XPL image, 2x (Field of view = 7mm)	Crinoids fragments in an Encrinite with green Glauconite. XPL image, 2x (Field of view = 7mm)	Crinoids fragments in an Encrinite with green Glauconite. XPL image, 2x (Field of view = 7mm)
Crinoid fragment with calcite syntaxial overgrowth. XPL image, 10x (Field of view = 2mm)	Crinoid fragment with calcite syntaxial overgrowth. XPL image, 10x (Field of view = 2mm)	Crinoid fragment with calcite syntaxial overgrowth. XPL image, 10x (Field of view = 2mm)
Crinoid fragment with calcite syntaxial overgrowth. Immagine a NX, 10x (lato lungo = 2mm)	Crinoid fragment with calcite syntaxial overgrowth. Immagine a NX, 10x (lato lungo = 2mm)	Crinoid fragment with calcite syntaxial overgrowth. Immagine a NX, 10x (lato lungo = 2mm)
Crinoid fragments with calcite syntaxial overgrowth. PPL image, 2x (Field of view = 7mm)	Crinoid fragments with calcite syntaxial overgrowth. XPL image, 2x (Field of view = 7mm)	Crinoid fragments with calcite syntaxial overgrowth. XPL image, 10x (Field of view = 2mm)
Crinoid fragments with calcite syntaxial overgrowth. PPL image, 10x (Field of view = 2mm)	Crinoid fragments with calcite syntaxial overgrowth. XPL image, 10x (Field of view = 2mm)	Crinoid fragments with calcite syntaxial overgrowth. XPL image, 10x (Field of view = 2mm)