Oil shale and Porphyry Types and Facts
Types
Carbonate-rich Shale, Siliceous Shale and Cannel Shale
Rhomb Porphyry
Features
Easily splits into thin plates, Generally rough to touch, Is one of the oldest rock, Very fine grained rock
Generally rough to touch, Is one of the oldest rock, Surfaces are often shiny
Archaeological Significance
Monuments
Not Yet Used
Used
Famous Monuments
Not Applicable
Data Not Available
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
Types of Oil shale and Porphyry
Some rocks according to their use or texture are classified into different types. Know more about Oil shale Texture and Porphyry Texture. Types of Oil shale are Carbonate-rich Shale, Siliceous Shale and Cannel Shale whereas the types of Porphyry are Rhomb Porphyry.During historic times, some rocks depending on their hardness were used to create Pictographs and Petroglyphs. Rocks which are hard were generally not used. Pictographs are paintings or drawings that have been placed or created on the surface of rock. Oil shale and Porphyry were not used for creating pictographs. Petroglyph is an image which is carved into a rock. These are images created by removing part of a rock surface by incising, picking, carving or abrading, as a form of rock art. Oil shale and Porphyry were not used for creating petroglyphs.