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s containing considerable iron. Also used as a general term to include the whole species. Hornblende schist (Geol.), a hornblende rock of schistose structure.

y aluminium and iron. Some common varieties are tremolite, actinolite, asbestus, edenite, hornblende (the last name being also used as a general term for the whole species). Amphibole is a constituent of many crystalline rocks, as syenite, diorite, most varieties of trachyte, etc. See Hornblende.

e rock allied to trachyte, consisting essentially of a triclinic feldspar, with pyroxene, hornblende, or hypersthene.

A mineral of the hornblende group, of a yellowish gray or clove brown color. -- An`tho*phyl*lit"ic, a.

An olive-green fibrous variety of hornblende.

A mineral occuring in silky fibers of a lavender blue color. It is related to hornblende and is essentially a silicate of iron and soda; -- called also blue asbestus. A silicified form, in which the fibers penetrating quartz are changed to oxide of iron, is the yellow brown tiger-eye of the jewelers.…

An igneous, crystalline in structure, consisting essentially of a triclinic feldspar and hornblende. It includes part of what was called greenstone.

A rock consisting of granular red garnet, light green smaragdite, and common hornblende; -- so called in reference to its beauty.

s or slabs, which is due to the cleavage structure of one of the constituents, as mica or hornblende. It may sometimes include slaty structure or cleavage, though the latter is usually independent of any mineral constituent, and transverse to the bedding, it having been produced by pressure.

the mica, arranged in planes, so that it breaks rather easily into coarse slabs or flags. Hornblende sometimes takes the place of the mica, and it is then called hornblendic or syenitic gneiss. Similar varieties of related rocks are also called gneiss.

Composed largely of hornblende; resembling or relating to hornblende.

A dark green aluminous variety of amphibole, or hornblende.

A dark green igneous rock, consisting largely of chrysolite, with hornblende, augite, biotite, etc.

kinds are mica schist, and hornblendic schist, consisting chiefly of quartz with mica or hornblende and often feldspar.

uminous slate (Min.), a soft species of sectile clay slate, impregnated with bitumen. -- Hornblende slate (Min.), a slaty rock, consisting essentially of hornblende and feldspar, useful for flagging on account of its toughness. -- Slate ax or axe, a mattock with an ax end, used in shaping slates for roofs, and making…

. -- Slaty gneiss (Min.), a variety of gneiss in which the scales of mica or crystals of hornblende, which are usually minute, form thin laminæ, rendering the rock easily cleavable.

Containing hornblende in a scattered state; of or relating to rocks containing disseminated hornblende.

Orig., a rock composed of quartz, hornblende, and feldspar, anciently quarried at Syene, in Upper Egypt, and now called granite.

breaking with a rough surface. It consists chiefly of orthoclase feldspar with sometimes hornblende and mica.

A white variety of amphibole, or hornblende, occurring in long, bladelike crystals, and coarsely fibrous masses.