coloured art glass isn't really my area, but I get the impression that this fractured/fissured decorative effect must have been popular between the two world wars ......... I see that the Scottish Monart appear to have made use of it, and believe those pieces are referred to as 'Cloisonné', but not certain.
Not quite sure how the name of an intaglio enamelled process on metalwork transfers to glass, but there's no end to peoples' inventiveness.

Am sure I've also seen a similar decorative effect on some big name Continental makes, but can't remember names now.