Help me identify this piece - is it Loetz?

This lovely irridescent bowl with pink and yellow threads was bought at a reputable auction, where it was offered as a Loetz piece. Unfortunately there is no signature. It has a ground and polished pontil mark - clearly evident that it is hand-made, probably in the late 1800's to the early 1900's. I've looked through the various decors of Loetz on-line and have not seen anything quite like it. It is in excellent condition - no chips, cracks or broken threads. I would appreciate any help in identifying this bowl and any suggestion as to it's value.