Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Framboidal polycrystalline aggregation

Colloform general term for botryoidal. mamillary, reniform with banded texture [Pg.157]

Spherulite formation by geometrical selection may rarely be seen on crystals with isotropic Habitus. Native arsenic. As, occurs in a confeito-like form, and is a type of spherulite grown through the geometrical selection of rhombohedral crystals. Spherical aggregation of calcite crystals with nail-head Habitus is also observed. Semi-spherical aggregates of platy barite crystals known as desert rose are shown in Fig. 8.6. [Pg.157]

There is a type of polycrystalline aggregate of pyrite crystals showing a framboidal appearance, known as framboidal pyrite. It occurs in sedimentary [Pg.157]


Framboidal polycrystalline aggregation 157 Table 8.1 Terms used to describe textures of polycrystalline aggregates... [Pg.157]

P5U ite crystals exhibit a wide range of Tracht and Habitus, and also occur in unusual forms of polycrystalline aggregate, such as framboidal pyrite. Although numerous crystal faces have been reported, the most important ones are 100, 111, and 210. Calcite also exhibits a variety of Tracht and Habitus, such as platy, nail-head, prismatic, or dog-tooth forms, but 1011 is the only F face. In this chapter, we focus our attention on the factors controlling the observed variations in Tracht and Habitus of p3U ite and calcite. [Pg.225]


See other pages where Framboidal polycrystalline aggregation is mentioned: [Pg.230]    [Pg.230]    [Pg.226]   


SEARCH



Framboids

Polycrystalline

Polycrystalline aggregate

Polycrystallines

Polycrystallinity

© 2024 chempedia.info