Definition
Pumice is a volcanic rock that consists of highly vesicular rough textured volcanic glass, which may or may not contain crystals
Dacite is a volcanic igneous rock which is rintermediate in composition between andesite and rhyolite
Origin
Spain
Romania and Moldova, Europe
Discoverer
Unknown
Unknown
Etymology
From Old French pomis, from a Latin dialect variant of pumex
From Dacia, a province of the Roman Empire which lay between the Danube River and Carpathian Mountains where the rock was first described
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Soft Rock
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Vesicular
Aphanitic to Porphyritic
Color
Beige, Grey, Light Green, Light Grey, Pink, White, Yellow- grey
Bluish - Grey, Brown, Grey, Light to Dark Grey
Durability
Durable
Durable
Appearance
Vesicular
Vesicular
Interior Uses
Decorative Aggregates, Flooring, Homes, Interior Decoration
Decorative Aggregates, Entryways, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
As Building Stone, Paving Stone, Garden Decoration
Other Architectural Uses
Curbing, Powder
Curbing
Construction Industry
As Dimension Stone, Cement Manufacture, for Road Aggregate, In landscaping and horticulture, Making natural cement, Production of lightweight concrete blocks
As Dimension Stone, Construction Aggregate, for Road Aggregate, Landscaping
Medical Industry
As an abrasive in skin exfoliating products, In Chemical and Pharmaceutical Industry, Medicines and Cosmetics
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Antiquity Uses
Artifacts
Artifacts
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
Commemorative Tablets, Creating Artwork
Types
Scoria
Footwall Dacite, Hanging wall Dacite, Tuff and Biotite Dacite
Features
Host Rock for Lead
Host Rock for Lead, Is one of the oldest rock
Archaeological Significance
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.
Dacitic magma is formed by the subduction of young oceanic crust under a thick felsic continental plate. Further, the Oceanic crust is hydrothermally altered as quartz and sodium are added.
Mineral Content
Aluminum Oxides, Calcite, Carbonate, Iron Oxides, Silica
Amphibole, Apatite, Biotite, Feldspar, Garnet, Hornblade, Magnetite, Plagioclase, Pyroxene, Quartz, Zircon
Compound Content
Al, Aluminium Oxide, CaO, Carbon Dioxide, MgO, Silicon Dioxide
Ca, Fe, Potassium Oxide, Mg, Potassium, Silicon Dioxide
Types of Metamorphism
Burial Metamorphism, Impact Metamorphism
Burial Metamorphism, Cataclastic Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Chemical Erosion
Grain Size
Fine Grained
Medium to Fine Coarse Grained
Fracture
Planar
Conchoidal
Streak
White, Greenish White or Grey
White
Porosity
Highly Porous
Less Porous
Luster
Earthy
Subvitreous to Dull
Specific Gravity
2.86
2.86-2.87
Transparency
Opaque
Translucent
Density
0.25-0.3 g/cm3
2.77-2.771 g/cm3
Resistance
Impact Resistant, Pressure Resistant
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
Afghanistan, Indonesia, Japan, Russia
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Africa
Ethiopia, Kenya, Tanzania
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Europe
Greece, Hungary, Iceland, Italy, Turkey
France, Greece, Romania, Scotland, Spain
Deposits in Western Continents
North America
Bahamas, Barbados, Canada, Costa Rica, Cuba, Jamaica, Mexico, USA
USA
South America
Argentina, Chile, Ecuador, Peru
Argentina, Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
Deposits in Oceania Continent
Australia
New Zealand, Western Australia
New Zealand, South Australia, Western Australia
All about Pumice and Dacite Properties
Know all about Pumice and Dacite properties here. All properties of rocks are important as they define the type of rock and its application. Pumice and Dacite belong to Igneous Rocks.Texture of Pumice is Vesicular whereas that of Dacite is Aphanitic to Porphyritic. Pumice appears Vesicular and Dacite appears Vesicular. The luster of Pumice is earthy while that of Dacite is subvitreous to dull. Pumice is available in beige, grey, light green, light grey, pink, white, yellow- grey colors whereas Dacite is available in bluish - grey, brown, grey, light to dark grey colors. The commercial uses of Pumice are 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 and that of Dacite are commemorative tablets, creating artwork.