An obsolete varietal term for manganoan zincian chamosite.
See chlorite

An ammonia-dominated feldspar mineral, NH₄(Si₃Al)O₈.
Cf., alkali feldspar, feldspar, plagioclase feldspar

A poorly defined material, possibly biotite and vermiculite or interlayer-deficient biotite.

See astrophyllite group.

A measure of the resistance of a material to external stress, in units of pressure (usually gigapascals), by fitting the incremental change in potential energy with incremental change in volume (e.g., Birch-Murnaghan equation of state). The bulk modulus is measured by experiments or by simulations and best describes isotropic materials.
Cf., elastic constant.

A synthetic phase.
See birnessite

See plagioclase feldspar.

Stoops and Jongerius (1975) differentiated five characteristic types (e.g., fabrics) of soil and palustrine deposits based on coarse (c) and fine (f) or clay particles: monic, gefuric, cithonic, enaulic, and porphyric. The c/f related distribution is therefore the relationship between ground mass (matrix) and a general framework of coarser components (e.g. grains, aggregates). The different descriptions of the classifications, however, are not mutually exclusive:

– cithonic c/f-related distribution : A distribution where fine-grained material forms a wrap over the coarser skeletal components. Any orientation of the clay particles in the wrap or cover are not considered important in the definition.

– enaulic c/f-related distribution : A distribution where there is a framework of grain- supported skeletal components with partial infillings of fine grained materials and pore spaces.

– gefuric c/f-related distribution : The distribution involves fine-grained material connecting coarser components, where coarse material is not in direct contact with other coarse components.

– monic c/f-related distribution : This distribution consists of predominantly one size group, including all ground mass, amorphous material or skeletal components.

– porphyric c/f-related distribution : The distribution of generally coarse components within a ground mass of fine-grained material.

An obsolete varietal term for biotite.

See reyerite group.