Definition
Scoria is a dark-colored extrusive igneous rock with abundant round bubble-like cavities
Marl is an unconsolidated sedimentary rock consisting of clay and lime
Discoverer
Unknown
William Smith
Etymology
From late Middle English (denoting slag from molten metal), from Greek skōria refuse, from skōr dung
From Old French marle, from Late Latin marglia
Class
Igneous Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Soft Rock
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Color
Black, Brown, Dark Grey to Black, Red
Beige, Brown, Green, Grey, White
Durability
Durable
Durable
Appearance
Glassy and Vesicular
Rough and Dull
Interior Uses
Decorative Aggregates, Interior Decoration
Decorative Aggregates, Floor Tiles
Exterior Uses
Garden Decoration, Paving Stone
As Building Stone, Roof Tiles
Other Architectural Uses
Curbing
Curbing
Construction Industry
Cement Manufacture, Construction Aggregate, for Road Aggregate, In landscaping and drainage works
Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, Raw material for the manufacture of mortar
Antiquity Uses
Artifacts, Monuments, Sculpture
Artifacts, Jewellery, Sculpture, Small Figurines
Commercial Uses
As a traction material on snow-covered roads, Creating Artwork, High-temperature insulation, In gas barbecue grills
Creating Artwork, Soil Conditioner
Types
Basaltic Scoria and Andesitic Scoria
Clay Marl ,Blue Marl, Red Marl, High Bank Marl, Shell Layer Marl, Under Shell Layer Marl, Sand Marl, Green Marl, Grey Marl and Clayey Marl
Features
Available in Lots of Colors and Patterns, Generally rough to touch, Surfaces are often shiny
Generally rough to touch, Is one of the oldest rock, Splintery, Very fine grained rock
Archaeological Significance
Formation
Scoria forms when magma containing huge amount of dissolved gas flows from a volcano during an eruption.
Marl forms when very fine-grained clay particles are deposited in water which settles at the bottom of water bodies and are compacted by overlying sediment; the water squeezes out and hence forming Marl rock.
Mineral Content
Apatite, Biotite, Calcite, Feldspar, Hematite, Hornblade, Ilmenite, Magnetite, Olivine, Pyroxene, Quartz, Silica
Calcite, Clay, Dolomite, Gypsum, Micas, Pyrite, Quartz
Compound Content
Ca, NaCl
Aluminium Oxide, NaCl, CaO, Iron(III) Oxide, Silicon Dioxide
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
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Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Chemical Erosion, Coastal Erosion, Water Erosion, Wind Erosion
Grain Size
Fine Grained
Very fine-grained
Fracture
Conchoidal
Conchoidal
Porosity
Highly Porous
Highly Porous
Luster
Subvitreous to Dull
Dull
Specific Gravity
-9999
2.2-2.8
Transparency
Opaque
Opaque
Density
-9999 g/cm3
2.4-2.8 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Impact Resistant
Deposits in Eastern Continents
Asia
Afghanistan, Indonesia, Japan, Russia
India, Pakistan, Russia
Africa
Ethiopia, Kenya, Tanzania
Ethiopia, Kenya, Morocco, South Africa
Europe
Greece, Hungary, Iceland, Italy, Turkey
Austria, France, Germany, Greece, Italy, Romania, Scotland, Spain, Switzerland
Deposits in Western Continents
North America
Bahamas, Barbados, Canada, Costa Rica, Cuba, Jamaica, Mexico, USA
USA
South America
Argentina, Chile, Ecuador, Peru
Colombia, Ecuador, Peru
Deposits in Oceania Continent
Australia
New Zealand, Western Australia
New South Wales, Victoria, Western Australia