Thames shipping Ltd. Polla Rose is a 1971 Dutch built shortsea/river trader operated by Thames Shipping Ltd, a new subsidiary of Euromix Concrete. The vessel carries aggregates into Mohawk Wharf, Silvertown from JJ Prior's quarry at Fingringhoe, Essex.Previously named Geminus, the vessel was found by the skippers on the Manchester Ship Canal, where it was being advertised for sale as a possible houseboat conversion. It had been working there since 2002 in the inland grain trade for E Muller.