A rare earth mineral is a mineral that contains one or more rare earth elements as major metal constituents.Rare earth minerals are usually found in association with alkaline to peralkaline igneous complexes, in pegmatites associated with alkaline magmas and in or associated with carbonatite intrusives.Perovskite mineral phases are common hosts to rare earth elements within the alkaline complexes.he following includes the relatively common hydrothermal rare earth minerals and minerals that often contain significant rare earth substitution: 1  aeschynite. 2  allanite. 3  apatite. 4  bastnaesite. 5  bastnÃ¤site. 6  britholite. 7  brockite. 8  cerite. 9  fluocerite. 10  fluorite. 11  gadolinite. 12  monazite. 13  parisite. 14  stillwellite. 15  synchysite. 16  titanite. 17  wakefieldite. 18  xenotime.  zircon
A boat is a watercraft of a large range of sizes designed to float, plane, work or travel on water. Small boats are typically found on inland waterways (e.g., rivers and lakes) or in protected coastal areas. However, boats such as the whaleboat were designed for operation from a ship in an offshore environment. In naval terms, a boat is a vessel small enough to be carried aboard another vessel (a ship).
Keelboats were generally built in Pittsburgh, Pennsylvania and it was here that Meriwether Lewis commissioned the boat used by the Corps of Discovery. The keelboat used by the Corps was sketched by Clark in his journal. It was 55 feet long and 8 feet wide, with a 3- to 4-foot draft. For propulsion it had a 32-foot sailing mast, 22 oars, a rudder, and a tiller for steering. Protection against hostile encounters were a swivel cannon on the bow and two smaller guns called blunderbusses.