Undentified Shell Basket

[kopetz]

Hi there -
I inherited a shell basket from my grandma, who claimed it was an "antique".  However, I'm having trouble finding something similiar on the internet, even a similar shell. I'm guessing it is a freshwater shell?  The basket is made with wire.  My mom said she saw a similiar one in a Native American art shop, worth about $150.  Thoughts?  Thanks so much!!

<a href="http://www.badongo.com/pic/764626" target="_blank"><!-- m --><a class="postlink" href="http://www.badongo.com/pic/764626">http://www.badongo.com/pic/764626</a><!-- m --></a>
<a href="http://www.badongo.com/pic/764632" target="_blank"><!-- m --><a class="postlink" href="http://www.badongo.com/pic/764632">http://www.badongo.com/pic/764632</a><!-- m --></a>

Kim