Definition
Pumice is a volcanic rock that consists of highly vesicular rough textured volcanic glass, which may or may not contain crystals
Mudstone is a fine-grained, dark gray sedimentary rock, which is formed from silt and clay and is similar to shale but has less laminations
History
Origin
Spain
-
Discoverer
Unknown
William Smith
Etymology
From Old French pomis, from a Latin dialect variant of pumex
From the English mud and stone, from low German mudde and stainaz
Class
Igneous Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Soft Rock
Family
Group
Volcanic
-
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Vesicular
Clastic
Color
Beige, Grey, Light Green, Light Grey, Pink, White, Yellow- grey
Black, Blue, Brown, Green, Grey, Orange, Red, White, Yellow
Maintenance
Less
Less
Durability
Durable
Durable
Water Resistant
✔
✘
✔
✘
Scratch Resistant
✔
✘
✔
✘
Stain Resistant
✔
✘
✔
✘
Wind Resistant
✔
✘
✔
✘
Acid Resistant
✔
✘
✔
✘
Appearance
Vesicular
Rough and Dull
Architecture
Interior Uses
Decorative Aggregates, Flooring, Homes, Interior Decoration
Decorative Aggregates, Entryways, Floor Tiles, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
As Building Stone, As Facing Stone, Paving Stone, Roof Tiles
Other Architectural Uses
Curbing, Powder
Curbing
Industry
Construction Industry
As Dimension Stone, Cement Manufacture, for Road Aggregate, In landscaping and horticulture, Making natural cement, Production of lightweight concrete blocks
Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, Raw material for the manufacture of mortar
Medical Industry
As an abrasive in skin exfoliating products, In Chemical and Pharmaceutical Industry, Medicines and Cosmetics
-
Antiquity Uses
Artifacts
Sculpture, Small Figurines
Other Uses
Commercial Uses
As a traction material on snow-covered roads, As an abrasive in pencil erasers, Fine abrasive used for polishing, Manufacture of Soap, Solvents, Dyes, Plastics and Fibres, Used in aquariums
Creating Artwork, Pottery
Types
Scoria
Marl, Shale and Argillite
Features
Host Rock for Lead
Available in Lots of Colors and Patterns, Smooth to touch, Very fine grained rock
Archaeological Significance
Monuments
-
-
Famous Monuments
-
-
Sculpture
-
-
Famous Sculptures
-
-
Pictographs
-
-
Petroglyphs
-
-
Figurines
-
-
Fossils
Absent
Present
Formation
Pumice rock forms when the magma cools so quickly that atoms in the melt are not able to arrange themselves into a crystalline structure.
Mudstone forms when very fine-grained clay particles are deposited in water which settle at the bottom of water bodies. They are buried and compacted by overlying sediment hence forming mudstone.
Composition
Mineral Content
Aluminum Oxides, Calcite, Carbonate, Iron Oxides, Silica
Biotite, Chlorite, Feldspar, Micas, Muscovite or Illite, Plagioclase, Pyrite, Quartz
Compound Content
Al, Aluminium Oxide, CaO, Carbon Dioxide, MgO, Silicon Dioxide
Aluminium Oxide, NaCl, CaO, Iron(III) Oxide, Silicon Dioxide
Transformation
Metamorphism
✔
✘
✔
✘
Types of Metamorphism
Burial Metamorphism, Impact Metamorphism
-
Weathering
✔
✘
✔
✘
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Chemical Weathering, Mechanical Weathering
Erosion
✔
✘
✔
✘
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Sea Erosion
Physical Properties
Hardness
62-3
1
7
👆🏻
Grain Size
Fine Grained
Very fine-grained
Fracture
Planar
-
Streak
White, Greenish White or Grey
White
Porosity
Highly Porous
Highly Porous
Luster
Earthy
Dull
Compressive Strength
51.20 N/mm225.00 N/mm2
0.15
450
👆🏻
Cleavage
Perfect
Perfect
Toughness
3
2.6
Specific Gravity
2.862.2-2.8
0
8.4
👆🏻
Transparency
Opaque
Opaque
Density
0.25-0.3 g/cm32.4-2.8 g/cm3
0
1400
👆🏻
Thermal Properties
Specific Heat Capacity
0.87 kJ/Kg K0.39 kJ/Kg K
0.14
3.2
👆🏻
Resistance
Impact Resistant, Pressure Resistant
Heat Resistant, Impact Resistant
Deposits in Eastern Continents
Asia
Afghanistan, Indonesia, Japan, Russia
Bangladesh, China, India, Russia
Africa
Ethiopia, Kenya, Tanzania
Ethiopia, Kenya, Morocco, South Africa, Tanzania
Europe
Greece, Hungary, Iceland, Italy, Turkey
Austria, France, Germany, Greece, Italy, Romania, Scotland, Spain, Switzerland
Others
-
-
Deposits in Western Continents
North America
Bahamas, Barbados, Canada, Costa Rica, Cuba, Jamaica, Mexico, USA
USA
South America
Argentina, Chile, Ecuador, Peru
Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
Deposits in Oceania Continent
Australia
New Zealand, Western Australia
New South Wales, New Zealand, Queensland, Victoria, Western Australia