Chalcopyrite is common in hydrothermal vein deposits, contact metamorphic rocks, and disseminated in igneous andsedimentary rocks.
VISHAL HIRJI

Chemical FormulaBaSO4
Environment | In sedimentary rock layers and in hydrothermal and mesothermal metal ore veins. Rarely in altered basalts.
Rock Type | Sedimentary, Metamorphic
Popularity (1-4) | 2
Prevalence (1-3) 
VISHAL HIRJI

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Rock Type | Sedimentary, Metamorphic

Coal is organic sedimentary rock

All the Igneous

A well graded soil is a soil that contains particles of a wide range of sizes and has a good representation of all sizes from the No. 4 to No. 200 sieves. A well graded gravel is classified as GW while a well graded sand is classified as SW.

Gap grading is a kind of grading which lacks one or more intermediate size. Gap graded aggregates can make good concrete when the required workability is relatively low. Advantages of gap grading are more economical concrete, use of less cement and lower w/c ratios. When they are used in high workability mixes, segregation may become a problem. The resulting concrete is very stiff and has low workability. An extreme case is no-fines concrete. This concrete is difficult to handle and compact; developing low strength and high permeability.

For uniformly graded aggregate, only a few sizes dominate the bulk material. With this grading, the aggregates are not are not effectively packed, and the resulting concrete will be more porous, unless a lot of paste is employed.

Open graded aggregate contains too much small particles and easy to be disturbed by a hole.

 

n.Metamorphism in which the mineralogy and texture of a body of rock are changed by exposure to the pressure and extreme temperature associated with a body of intruding magma. Contact metamorphism often results in the formation of valuable minerals, such as garnet and emery, through the interaction of the hot magma with adjacent rock.VISHAL HIRJI