Definition
Novaculite is a dense, hard, fine-grained, siliceous metamorpic rock which is a type of chert that breaks with conchoidal fracture
  
Siltstone can be defined as a fine-grained sedimentary rock which mainly consists of consolidated silt
  
History
  
  
Discoverer
Unknown
  
Unknown
  
Etymology
From Latin word novacula, for razor stone
  
From English word silt and stone and from Proto-Indo-European root sal and stainaz
  
Class
Sedimentary Rocks
  
Sedimentary Rocks
  
Sub-Class
Durable Rock, Hard Rock
  
Durable Rock, Hard Rock
  
Family
  
  
Group
Not Applicable
  
Not Applicable
  
Other Categories
Fine Grained Rock, Opaque Rock
  
Fine Grained Rock, Opaque Rock
  
Texture
Banded, Glassy, Rough, Vitreous
  
Clastic
  
Color
Black, Brown, Green, Grey, Red, White
  
Brown, Red, Reddish Brown
  
Maintenance
Less
  
Less
  
Durability
Durable
  
Durable
  
Water Resistant
Yes
  
Yes
  
Scratch Resistant
Yes
  
Yes
  
Stain Resistant
Yes
  
No
  
Wind Resistant
Yes
  
Yes
  
Acid Resistant
Yes
  
Yes
  
Appearance
Glassy or Pearly
  
Rough
  
Architecture
  
  
Interior Uses
Countertops, Decorative Aggregates, Flooring, Interior Decoration
  
Decorative Aggregates, Interior Decoration
  
Exterior Uses
As Building Stone, Garden Decoration
  
As Building Stone, As Facing Stone, Garden Decoration
  
Other Architectural Uses
Curbing
  
Curbing
  
Industry
  
  
Construction Industry
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
  
Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, Raw material for the manufacture of mortar
  
Medical Industry
Not Yet Used
  
Not Yet Used
  
Antiquity Uses
Artifacts, Monuments
  
Artifacts, Sculpture, Small Figurines
  
Other Uses
  
  
Commercial Uses
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
  
Raw material for the manufacture of mortar, Soil Conditioner
  
Types
Not Available
  
Not Available
  
Features
Clasts are smooth to touch, Easily splits into thin plates, Has High structural resistance against erosion and climate
  
Available in Lots of Colors and Patterns, Easily splits into thin plates, Generally rough to touch, High silica content, Very fine grained rock
  
Archaeological Significance
  
  
Monuments
Used
  
Not Yet Used
  
Famous Monuments
Data Not Available
  
Not Applicable
  
Sculpture
Not Yet Used
  
Used
  
Famous Sculptures
Not Applicable
  
Data Not Available
  
Pictographs
Not Used
  
Not Used
  
Petroglyphs
Not Used
  
Not Used
  
Figurines
Not Yet Used
  
Used
  
Fossils
Present
  
Present
  
Formation
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.
  
Siltstone is a type of sedimentary rock which is formed from fine rock particles. As the particles of eroded rock travel along with water, the edges of the rock are worn-out by water into a rounded shape.
  
Composition
  
  
Mineral Content
Quartz, Silicon
  
Calcite, Clay, Clay Minerals, Feldspar, Micas, Quartz, Sand, Silica, Silt
  
Compound Content
Ca, Silicon Dioxide
  
Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide
  
Transformation
  
  
Metamorphism
No
  
No
  
Types of Metamorphism
Not Applicable
  
Not Applicable
  
Weathering
No
  
Yes
  
Types of Weathering
Not Applicable
  
Biological Weathering, Chemical Weathering, Mechanical Weathering
  
Erosion
Yes
  
Yes
  
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
  
Chemical Erosion, Coastal Erosion, Glacier Erosion
  
Physical Properties
  
  
Hardness
7
  
6-7
  
Grain Size
Fine Grained
  
Fine Grained
  
Fracture
Conchoidal
  
Conchoidal
  
Streak
Colorless
  
White
  
Porosity
Less Porous
  
Highly Porous
  
Luster
Waxy and Dull
  
Dull
  
Compressive Strength
450.00 N/mm
2
  
1
Not Available
  
Cleavage
Non-Existent
  
Not Available
  
Toughness
1.5
  
2.6
  
Specific Gravity
2.5-2.7
  
2.54-2.73
  
Transparency
Translucent to Opaque
  
Opaque
  
Density
2.7 g/cm3
  
2.6-2.7 g/cm3
  
Thermal Properties
  
  
Specific Heat Capacity
0.74 kJ/Kg K
  
19
Not Available
  
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
  
Heat Resistant, Impact Resistant, Pressure Resistant, Water Resistant
  
Deposits in Eastern Continents
  
  
Asia
China, India, Iran, Japan, Oman, Russia, Saudi Arabia, Taiwan, Thailand, Vietnam
  
China, India, Kazakhstan, Mongolia, Russia, Uzbekistan
  
Africa
Kenya, Morocco, South Africa, Tanzania
  
Namibia, Nigeria, South Africa
  
Europe
Austria, France, Greece, Italy, Malta, Poland, Portugal, Serbia, Spain, Sweden, United Kingdom
  
Austria, Denmark, Germany, Great Britain, Netherlands, Norway, Poland, Sweden, Switzerland, United Kingdom
  
Others
Greenland, Mid-Atlantic Ridge
  
Greenland
  
Deposits in Western Continents
  
  
North America
Canada, Mexico, USA
  
Canada, USA
  
South America
Bolivia, Brazil
  
Brazil
  
Deposits in Oceania Continent
  
  
Australia
New South Wales, Queensland, South Australia, Western Australia
  
New South Wales, New Zealand