Definition
Very fine grained fault rock which is composed of glassy matrix that often contains inclusions of wall-rock fragments.
Hornblendite is a type of igneous plutonic rock consisting mainly of amphibole hornblende and is a type of Amphibolite rock
Discoverer
Unknown
Unknown
Etymology
From pseudo- + tachylite, a glassy rock generated by frictional heat within faults.
From German, Horn horn + blende
Class
Metamorphic Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Quench
Banded, Foliated, Massive
Color
Black, Brown, Green, Grey, Pink, White
Black, Brown, Green, Grey
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Dull and Soft
Foliated
Interior Uses
Decorative Aggregates, Entryways, Interior Decoration
Countertops, Decorative Aggregates, Entryways, Flooring, Homes, Hotels, Interior Decoration, Kitchens
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Cement Manufacture, for Road Aggregate, Making natural cement
As Dimension Stone, Building houses or walls, Cobblestones, Construction Aggregate, for Road Aggregate, Landscaping, Production of Glass and Ceramics, Roadstone
Antiquity Uses
Artifacts, Monuments
Artifacts, Sculpture, Small Figurines
Commercial Uses
Creating Artwork, Gemstone
Cemetery Markers, Commemorative Tablets, Creating Artwork
Types
Cataclastic rock
Hornblende Gabbro and Hornblende Peridotite
Features
Host Rock for Lead
Clasts are smooth to touch, Matrix variable, Surfaces are often shiny
Archaeological Significance
Formation
Due to change in environmental conditions, rocks are heated and pressurized deep inside the Earth's surface. Pseudotachylite is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.
Hornblendite is a fine-grained, hard rock which is a type of metasomatite, essentially altered basalt. It forms with or without crystallization, either below the surface as intrusive rocks or on the surface as extrusive rocks.
Mineral Content
Iron Oxides, Pyroxene, Quartz, Stishovite, Sulfides
Amphibole, Calcite, Hornblade, Magnetite, Plagioclase, Wollastonite
Compound Content
Carbon Dioxide, Silicon Dioxide, Sulfur Dioxide, Sulphur
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
-
Types of Weathering
-
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
-
Chemical Erosion, Water Erosion, Wind Erosion
Grain Size
Very fine-grained
Medium to Coarse Grained
Fracture
Uneven
Irregular to Conchoidal
Streak
Light to dark brown
White to Grey
Porosity
Less Porous
Less Porous
Luster
Vitreous
Vitreous to Dull
Specific Gravity
2.46-2.86
2.5
Transparency
Transparent to Translucent
Opaque
Density
2.7-2.9 g/cm3
2.85-3.07 g/cm3
Resistance
Heat Resistant
Heat Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
South Korea
Russia, Turkey
Africa
Western Africa
Burundi, Djibouti, Eritrea, Ethiopia, Kenya, Madagascar, Rwanda, Somalia, South Africa, Sudan, Tanzania, Uganda
Europe
Great Britain, Switzerland
Germany, Greece, Iceland, Norway, Poland
Deposits in Western Continents
North America
-
Canada, USA
Deposits in Oceania Continent
Australia
Central Australia, Western Australia
South Australia, Western Australia