Vintage hand made puka shell necklace

Vintage hand made, graduated puka shell necklace. I grew up in Hawaii finding these shells and you just don't find as many anymore. You can tell that these are natural (natural holes) from the shape and spiral. Beautifully imperfect and one of a kind. 17" long, see other pics for measurements. These sell for a lot more than my listing process but it's time for me to sell it to make room for other treasures.