Bit of a condundrum with this bowl, as it's by neither of the two noted makers of wave-ribbed wares.
The quality is very ho-hum, with LOTS of frit, bubbles, striations, etc... and it also has a 'fake' pontil mark that is just a moulded indent. Faced with just these facts, I'd be quite tempted to say that it's fairly new, except that there's quite a bit of convincing wear on it and the glass doesn't 'feel' very new (hard to quantitate - but I know what I mean!

)
H= 10cm / 4"
D=26cm / 10.25"
Any clues?
(Apologies for the grainy pics - my lighting equipment is buried under a mound of decorating stuff so I had to rely on very grey daylight)