Topic: Bright green geode bowl with curious base finish

[flying free]

Little bowl - measures 4"wide (10cm) by 2" high(5cm)  and the rim width is 5/8" (2cm).  Polished rim, immaculate finish all over. If you run your finger around the rim on the inside there is a slight 'lip' where it curves in towards the walls under the rim.  It has a curious base finish.  Where does it come from? Is it contemporary mass produced?  doesn't matter to me but I'm interested because I expected it to have a flat polished base.
Any thoughts please?  Have you seen them stacked up in piles in a homewares store somewhere?  thanks for any help.
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