Bohemian Art Nouveau cased glass vase - Rindskopf Aventurine

Yesterday I attended the now bi - monthly antiques fair. After a good walk around, I started examining things in more detail, & that's when I discovered this very unusual & special vase.
It measures 15 cm tall, 6 cm across the four way crimped top rim, & 5 cm across the base, which has a rough snapped pontil mark.
The vase is made from two layers of cased glass, the interior being a deep brick red, & the outer layer green with aventurine.
At the time, I didn't know what it was other than Bohemian & from the Art Nouveau era...& that it was an absolute must have. It simply oozed style & class. The form is languidly organic, with three indented sides & a cupped top.
The colour combination is rich & complex, & changes dramatically in different types of light.
After a little research, I found that it is an example of Rindskopf Aventurine.
Circa 1900.