Definition
Migmatite is typically a granitic rock within a metamorphic host rock which is composed of two intermingled but distinguishable components
Novaculite is a dense, hard, fine-grained, siliceous metamorpic rock which is a type of chert that breaks with conchoidal fracture
History
Origin
Southern Alps, France
-
Discoverer
Jakob Sederholm
Unknown
Etymology
From the Greek word migma which means a mixture
From Latin word novacula, for razor stone
Class
Metamorphic Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Family
Group
-
-
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Foliated
Banded, Glassy, Rough, Vitreous
Color
Black, Bluish - Grey, Brown, Brown- Black, Dark Greenish - Grey, Dark Grey to Black
Black, Brown, Green, Grey, Red, White
Maintenance
More
Less
Durability
Durable
Durable
Water Resistant
✔
✘
✔
✘
Scratch Resistant
✔
✘
✔
✘
Stain Resistant
✔
✘
✔
✘
Wind Resistant
✔
✘
✔
✘
Acid Resistant
✔
✘
✔
✘
Appearance
Dull, Banded and Foilated
Glassy or Pearly
Architecture
Interior Uses
Countertops, Flooring, Kitchens
Countertops, Decorative Aggregates, Flooring, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone
As Building Stone, Garden Decoration
Other Architectural Uses
Curbing
Curbing
Industry
Construction Industry
As Dimension Stone, Cement Manufacture, for Road Aggregate, Making natural cement
Arrowheads, Building houses or walls, Cement Manufacture, Construction Aggregate, Cutting Tool, for Road Aggregate, Knives, Landscaping, Making natural cement, Production of Glass and Ceramics, Rail Track Ballast, Roadstone, Spear Points, Used to sharpen metal tools and weapons
Medical Industry
-
-
Antiquity Uses
Artifacts
Artifacts, Monuments
Other Uses
Commercial Uses
Cemetery Markers, Jewelry, Tombstones, Used to manufracture paperweights and bookends
Cemetery Markers, Gemstone, In aquifers, In fire-starting tools, Jewelry, Manufacture of tools, Pebbles are used in ball mills to grind in ceramics industry, To determine the gold content of jewelry
Types
Diatexites and Metatexites
Sedimentary rock
Features
Generally rough to touch, Is one of the oldest rock
Clasts are smooth to touch, Easily splits into thin plates, Has High structural resistance against erosion and climate
Archaeological Significance
Monuments
-
-
Famous Monuments
-
-
Sculpture
-
-
Famous Sculptures
-
-
Pictographs
-
-
Petroglyphs
-
-
Figurines
-
-
Fossils
Absent
Present
Formation
Migmatites form by high temperature regional and thermal metamorphism of protolith rocks where rocks melt partially due to high temperature.
Novaculite forms when microcrystals of silicon dioxide grow within soft sediments that become limestone or chalk. The formation of Novaculite can be either of chemical or biological origin.
Composition
Mineral Content
Biotite, Chlorite, Feldspar, Garnet, Graphite, Hornblade, Micas, Muscovite or Illite, Quartz, Quartzite, Silica, Zircon
Quartz, Silicon
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, Silicon Dioxide
Transformation
Metamorphism
✔
✘
✔
✘
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Regional Metamorphism
-
Weathering
✔
✘
✔
✘
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
-
Erosion
✔
✘
✔
✘
Types of Erosion
Chemical Erosion, Glacier Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Physical Properties
Hardness
5.5-6.57
1
7
👆🏻
Grain Size
Medium to Fine Coarse Grained
Fine Grained
Fracture
Irregular
Conchoidal
Streak
White
-
Porosity
Very Less Porous
Less Porous
Luster
Dull to Pearly to Subvitreous
Waxy and Dull
Compressive Strength
120.00 N/mm2450.00 N/mm2
0.15
450
👆🏻
Cleavage
-
-
Toughness
1.2
1.5
Specific Gravity
2.65-2.752.5-2.7
0
8.4
👆🏻
Transparency
Opaque
Translucent to Opaque
Density
-9999 g/cm32.7 g/cm3
0
1400
👆🏻
Thermal Properties
Specific Heat Capacity
0.79 kJ/Kg K0.74 kJ/Kg K
0.14
3.2
👆🏻
Resistance
Heat Resistant, Pressure Resistant
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
China, India, Iran, Iraq, Kazakhstan, Kyrgyzstan, Mongolia, Russia
China, India, Iran, Japan, Oman, Russia, Saudi Arabia, Taiwan, Thailand, Vietnam
Africa
Cameroon, Ethiopia, Ghana, Kenya, Madagascar, Morocco, Mozambique, Namibia, Nigeria, Tanzania, Togo
Kenya, Morocco, South Africa, Tanzania
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
Austria, France, Greece, Italy, Malta, Poland, Portugal, Serbia, Spain, Sweden, United Kingdom
Others
-
Greenland, Mid-Atlantic Ridge
Deposits in Western Continents
North America
Canada, Costa Rica, Cuba, Mexico, Panama, USA
Canada, Mexico, USA
South America
Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Peru, Venezuela
Bolivia, Brazil
Deposits in Oceania Continent
Australia
New South Wales, New Zealand, Queensland, Victoria
New South Wales, Queensland, South Australia, Western Australia