Sedimentary Rock Identification Chart
sample
number
16
clastic/nonclastic
Clastic
5
Non-clastic
19
composition
grain size
structures present
rock name
Shell fragments
Greater than
2mm
None
Coquina
None
Glassy
Chert
Non-clastic
Organic material
Microcrystalline
quartz
Microcrystalline
Less than 1mm
None
Chert
17
Clastic
Rock fragments
1/16-2mm
Rough texture
Lithic sandstone
4
Clastic
Mostly clay
None
None
Claystone
6
Non-clastic
Microscopic
minerals
None
Small crystals
Ironstone
18
Clastic
Rock fragments
Greater than
2mm
None
Breccia
22
Non-clastic
Less than 1/16
Small crystals
Rock Salt
20
Clastic
Microcrystalline
Halite mineral
crystals
Sea shell
fragments
None
Shell fragments
Coquina
23
Non-clastic
Microcrystalline
None
None
Chert
sample
number
2
clastic/nonclastic
Non Clastic
1
composition
grain size
structures present
rock name
Calcite Crystals
None
None
Travertine
Clastic
Deterial
sediment
Greater than
2mm
Poorly sorted grains
Conglomerate
7
Non-clastic
Iron bearing
minerals
None
Microcrystalline
nodules
Ironstone
8
Non-Clastic
Charcoal
None
Black and layered
Bituminous Coal
10
Non-Clastic
Microcrystalline
dolomite
None
None
Dolostone
11
Non-Clastic
Microcrystalline
calcite/aragonite
None
None
Travertine
21
Clastic
Mostly rock
fragments
1/16-2mm
Porphyritic texture
Lithic Sandstone
13
Clastic
Calcareous
microfossils
None
Microscopic shells
Chalk
14
Non-Clastic
Microcrystalline
calcite/aragonite
Less than 2mm
None
Oolitic Limestone
9
Non-Clastic
Gypsum mineral
crystals
None
Visible crystals
Rock Gypsum