Handmade Designer Necklaces - Pearl and Swarovski crystal

I like colored unconventional luminous pearls.  A few years ago, they were plentiful.  Now for some reason they are hard to find.   The tear shaped  pearls above are many shades of green, blue and violet.  Most likely they were dyed to get this intense coloration.  The natural pearl colors are white and shades of pink or gray. 
These are fresh water cultured pearls. It is possible that the irritant was placed in a clam or oyster shell and the nacre of the shell covered the irritant and produced the shape and color.  After that it was dyed to enhance the original color.