Good thread here bsit1361 ,..
Here are some of mine from So. Cali . Typed as Costal Cottonwood's . Not to be confused with the "common" cottonwood , as I believe both types are discribed as having concaved to straight base ,./ concave to convex sides ,.

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Anyway ,. heres the long & short of the Costal Cottonwood ,. Don't believe I've ever seen one longer then 1 3/4 in. the shortest about 3/8 in. It is the one on the dime in the center .I'd say on avarage 3/4 in. is the norm . The big white quartz one on the left ,. I assume is a blade ,. and on the far right , the narrow white quartz ,. a drill,. as is the lit' clear one above it ,.. that is ,. a Costal Cottonwood drill
Now , here's a wee Cali Factoid about triangle points
Ishi ,.. the last stone age man in America ,.. A.K.A the "Last Wild Indian" . While living in the Anthroplogy Dept. at the University of California Berkeley [1911- 1916 ??]. Ishi was shown a collection of triangle points [maybe Costal Cottonwood's ?] being a polite man ,..said they were nice ,...but they where unfinished , but if they wished ,.. he could notch 'em and finish 'em up for them ,.. Good guy ,. Not often you find a stone age man willing to "clean-up " your collection for ya ..

,.. Believe they declined ??
True,.. best as memery serves anyway?? Blindpig