Here are some pictures of the unique trial piece made by Timothy Harris for the Royal Brierley 'Studio' range in 1986. It is about 17.5 cm high x 16.5 cm in diameter. The signature says 'TMH Nov 86 ©'. The vase was formerly in the Mark Hill collection.
You can see the similarity to IOWSG 'Lace' (
http://iowstudioglass.wikidot.com/lace), which was actually produced a couple of years later than this trial piece. To be honest, I hadn't realised that the Royal Brierley trial came before Lace until now.
Anton