Soil mechanics weathering of feldspar, which is the most common mineral present in igneous rock. The most common mineral constituent of silt and sand is quartz, also called silica, which has the chemical name silicon dioxide. The reason that feldspar is most common in rocks but silica is more prevalent in soils is that feldspar is much more soluble than silica. Silt, Sand, and Gravel are basically little pieces of broken rocks. According to the Unified Soil Classification System, silt particle sizes are in the range of 0.002 mm to 0.075 mm and sand particles have sizes in the range of 0.075
Granular pugolovka Granular pugolovka The granular pugolovka ("Benthophilus granulosus") is a species of gobiid fish widespread in the Caspian Sea. It is a small fish, with a length up to TL. It was listed as Least Concern by the IUCN in 2008: there are no known major threats. Granular pugolovkas are very abundant in their habitat due to their size and lack of natural predators. The common name 'pugolovka' is a Ukrainian word for tadpole. "Benthophilus granulosus" has a flat head with a flat barbel on the chin that is often described as being leathery. The body colors depend on the habitat