Three Generations Sixty Years Later

I would appreciate anyone with the knowledge if you can tell me what these pearls might be. After WWII my uncle brought them back returning from occupied Japan thru the Philippines where he had established a trading company for women's wear.

They were a gift to my mother. The strands are 22 inches long and there is also a pendant attached. They are at least 60+ years old and have a faint variable light blue lustre. I realize these are not perfectly rounds pearls and believe they are just what nature, made or were induced not as cultured as today, but you folks know more than I do.