Definition
Migmatite is typically a granitic rock within a metamorphic host rock which is composed of two intermingled but distinguishable components
Rhyolite is a fine-grained igneous rock which is rich in silica
Origin
Southern Alps, France
North America
Discoverer
Jakob Sederholm
Ferdinand von Richthofen
Etymology
From the Greek word migma which means a mixture
From German Rhyolit, from Greek rhuax lava stream + lithos stone
Class
Metamorphic Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Group
Not Applicable
Volcanic
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock
Texture
Foliated
Aphanitic, Glassy, Porphyritic
Color
Black, Bluish - Grey, Brown, Brown- Black, Dark Greenish - Grey, Dark Grey to Black
Grey, White, Light Black
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Dull, Banded and Foilated
Banded
Interior Uses
Countertops, Flooring, Kitchens
Decorative Aggregates, Homes, Hotels, Interior Decoration, Kitchens
Exterior Uses
As Building Stone, As Facing Stone
As Building Stone, As Facing Stone, Paving Stone, Office Buildings
Other Architectural Uses
Curbing
Not Yet Used
Construction Industry
As Dimension Stone, Cement Manufacture, for Road Aggregate, Making natural cement
Arrowheads, As Dimension Stone, Building houses or walls, Construction Aggregate, Cutting Tool, for Road Aggregate, Knives
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts
Artifacts
Commercial Uses
Cemetery Markers, Jewelry, Tombstones, Used to manufracture paperweights and bookends
Gemstone, Laboratory bench tops, Jewelry
Types
Diatexites and Metatexites
Pumice Rocks, Obsidian Rocks, Perlite Rocks, Porphyritic Rocks.
Features
Generally rough to touch, Is one of the oldest rock
Acidic in nature, Available in lots of colors
Archaeological Significance
Monuments
Not Yet Used
Not Yet Used
Famous Monuments
Not Applicable
Not Applicable
Sculpture
Not Yet Used
Not Yet Used
Famous Sculptures
Not Applicable
Not Applicable
Pictographs
Used
Not Used
Petroglyphs
Used
Not Used
Figurines
Not Yet Used
Not Yet Used
Formation
Migmatites form by high temperature regional and thermal metamorphism of protolith rocks where rocks melt partially due to high temperature.
Rhyolite is a felsic extrusive rock and due to its high silica content, rhyolite lava is very viscous and is volcanic equivalent of granite.
Mineral Content
Biotite, Chlorite, Feldspar, Garnet, Graphite, Hornblade, Micas, Muscovite or Illite, Quartz, Quartzite, Silica, Zircon
Biotite, Feldspar, Hornblade, Plagioclase, Pyroxene, Quartz
Compound Content
Aluminium Oxide, NaCl, CaO, Carbon Dioxide, Iron(III) Oxide, FeO, Potassium Oxide, Magnesium Carbonate, MgO, MnO, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Ca, Fe, Potassium Oxide, Mg, Potassium, Silicon Dioxide, Sodium
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Regional Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Glacier Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Sea Erosion, Water Erosion, Wind Erosion
Grain Size
Medium to Fine Coarse Grained
Large and Coarse Grained
Fracture
Irregular
Sub-conchoidal
Porosity
Very Less Porous
Highly Porous
Luster
Dull to Pearly to Subvitreous
Earthy
Compressive Strength
Not Available
Cleavage
Poor
Not Available
Specific Gravity
2.65-2.75
2.65-2.67
Transparency
Opaque
Opaque
Density
Not Available
2.4-2.6 g/cm3
Resistance
Heat Resistant, Pressure Resistant
Heat Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
China, India, Iran, Iraq, Kazakhstan, Kyrgyzstan, Mongolia, Russia
China, India
Africa
Cameroon, Ethiopia, Ghana, Kenya, Madagascar, Morocco, Mozambique, Namibia, Nigeria, Tanzania, Togo
Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa
Europe
Albania, Austria, Bosnia and Herzegovina, Finland, France, Georgia, Germany, Hungary, Italy, Kosovo, Monaco, Norway, Poland, Romania, Serbia, Slovakia, Slovenia, Sweden, Switzerland, Ukraine, United Kingdom
Germany, Iceland, Ireland, Italy, Spain
Others
Not Yet Found
Not Yet Found
Deposits in Western Continents
North America
Canada, Costa Rica, Cuba, Mexico, Panama, USA
Canada, USA
South America
Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Peru, Venezuela
Argentina, Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
Deposits in Oceania Continent
Australia
New South Wales, New Zealand, Queensland, Victoria
New Zealand, Queensland, Western Australia