The province is rich in mineral deposits. The glaciation removed as much as of sedimentary rocks from earlier inland sea deposits. Koriya is also known for its mineral deposits. Placer mining is the mining of stream bed (alluvial) deposits for minerals. Britain profited heavily from billions of dollars of Kuwaiti investments and bank deposits. Every sedimentary environment has its own characteristic deposits. The water thus gradually deposits the sediment as it runs, creating an alluvial plain. This spread covers operating costs for banks providing loans and deposits. The silver ore deposits they sought were soon underwater. Gold extraction is most economical in large, easily mined deposits. This turned out to contain Queensland's richest alluvial deposits. Coal power stations are in proximity to the coal deposits. Humboldt himself was keen to continue his studies of magnetism of mountains and mineral deposits. Coring began as a method of sampling surroundings of ore deposits and oil exploration. Mining is done from large boulders that contain bountiful deposits of jade.