The US Coast Guardâs largest patrol cutters are the 418 foot, 4,500 ton full load Bertholf Class National Security Cutters. The illustration that accompanies the story of the four new 5,000 ton cutters shows a ship, in many ways similar to the National Security Cutter. It appears there is a medium caliber gun on the bow.
Amphibolite is a rock composed mostly of amphibole minerals. Usually it's a hornblende schist like this as hornblende is the commonest amphibole.(more below). Amphibolite forms when basaltic rock is subjected to higher temperatures (550750Â°C) and slightly greater pressure range than that which yields greenschist.mphibolite is a rock composed mostly of amphibole minerals. Usually it's a hornblende schist like this as hornblende is the commonest amphibole. (more below).
The names of various schists are derived from their mineral constituents. For example, schists rich in mica are called mica schists and include biotite or muscovite. Most schists are mica schists, but graphite and chlorite schists are also common.chist forms at a higher temperature and has larger grains than phyllite. Geological foliation (metamorphic arrangement in layers) with medium to large grained flakes in a preferred sheetlike orientation is called schistosity.