Chapter 1 in Pearls A Practical Guide covers some basic facts about all pearls: their composition, hardness, the basic anatomy of a mollusc and ways to differentiate – for example, pearls with a bead nucleus or pearls which are all nacre, farmed (cultured) pearls or wild (natural) pearls or between sea and freshwater pearls.
What a love of pearls is all about.
The moment a beautiful gold south sea pearl is harvested.
So, it turns out oysters are great for the planet as well as for you. Oysters give you pearls, a meal and hyaluronic acid for your skin. Shells make buttons and mother of pearl. And the living mollusc cleans and enriches the planet. They’re as fabulous as bees!
Research in the seas around South Australia has shown that oysters provide shelter for small invertebrates, they trap water and give shelter at low tide, and, because they are filter feeders they improve water clarity. One oyster can filter 100 litres of water in a single day. The water is cleaner, and clearer, so more sunlight penetrates further down, and the oyster poop fertilises seafloor seaweeds and seagrass, creating a great habitat for more clams, worms and crabs as well as stability. Shoreline oyster reefs make for natural breakwaters. This could be particularly helpful in estuaries where high boat traffic intensifies shoreline erosion, such as Sydney Harbour.
sediments promote the growth of particular bacteria that convert excess organic nitrogen into inert nitrogen gas, thus preventing algal blooms that can harm other species. This process has been valued at more than $US4k per hectare per year..
Oysters’ filter-feeding is so efficient that Swedish researchers have evaluated it as a cost effective alternative to conventional mechanical wastewater treatment plants. Across the Atlantic, the loss of oyster reefs in Chesapeake Bay, the largest estuary on North America’s east coast, transformed the ecosystem from clear waters teeming with fish, to a murky, algae-choked mess.