(Information from Elisabeth Strack's book,
Pearls (© 2006)
, pages 611-613).
The culturing of blister pearls in abalone goes back to 1897, by the French scientist Louis Boutan.
Then in the early 1900s culturing trials began in California and by 1936 some blister pearls had been produced.
There seems to be a gap until Dr. Peter Fankboner began culturing
Haliotis in British Columbia, with success, leading to his founding Abalone Pearls of California. They cultured
Haliotis rufescens whose pearls had a "silver color with distinct green or pink overtones." (p. 612)
"It seems that the high expectations were not fulfilled, as regular production never took place. In 1998, there were three pearl farms in California, which had a franchise for Fankboner's method. In addition to the Abalone Pearls Company, there were the Monterey Abalone Company in Monterey and the North Coast Sea Farm in Crescent City belonging to Paul Cross."
Dr. David Leighton told Ms. Strack in 1998 that his company had begun culturing the green abalone,
Haliotis fulgens, "which has nacre layers with distinct blue and green overtones." (p. 612)
In 1999 the US Abalone Company harvested "several thousand cultured blister pearls of good quality." Its daughter company "Pearls of Passion" processed and made jewelry with the pearls and marketed them. (p. 613)
I looked up Dr. Fankboner, Pearls of Passion and some of the pearl companies Ms. Strack listed. It doesn't look like any of that work is still ongoing.
She wrote, "Another farm is reported to exist on the Pacific coast of Baja California in Mexico but no details are known." (p. 613) She must have been referring to Perlas del Mar de Cortez.
• I did find this thread with great photos in post 2 (sadly the photos in post 1 were from 3rd party hosting and were lost.)
A beautiful natural Red Abalone Pearl from the coast of California
• There is this 2000 article on abalone pearls from JCK magazine:
"Abalone Pearls"
https://www.jckonline.com/magazine-article/abalone-pearls/
• This thread from 2006 (the link in the first post doesn't work):
Abalone Pearl Culturing in British Columbia
• This about Dr. Fankboner:
https://network.expertisefinder.com/experts/peter-fankboner
• Finally, this 2014 thread:
California Abalone Pearl