Large-scale precipitations of sulphides, particularly those of zinc, iron and copper are common. These precipitates build up mounds and chimneys like tubes around the vent, these vents can grow up to 10 meters tall.

It has been estimated that for each 71cm3 of magma solidified the heat loss due to the circulating brines leads to the eventual deposition of 1 million tones of sulphide ore.

In fact, at some time in the future it maybe viable to mine these deposits, particularly as mineral deposits on the land are being used up rapidly. In a few years these deposits could become vital.

The ore deposits associated with these are not the only reason why these vents are important. Studies have found that the areas around the hydrothermal vents support a huge variety of life in a sunlight free environment. The life found in these places is unique. It was once thought that nothing could survive the harsh combinations of toxic chemicals, high pressures, high temperatures, and total darkness at these vents. Scientists have discovered huge tubeworms up to 4 feet tall anchored to the sea floor as well as mussels, shrimps, clams, and crabs. The fact that these animals are unique and we also know very little about them makes them so important. Around the vents enormous amounts of bacteria live and breed, they can withstand higher temperatures than any other organisms. This makes them attractive to researchers who are developing heat-stable enzymes for genetic engineering, and culturing bacteria designed to break down toxic waste.