Mount Surprise is a small township about 200 km SW of Cairns between Mount Garnet and Georgetown on the Gulf Developmental Road.
The locality is an old tin mining area, several kilometres in extent, now set aside for collectors. The tin miners ignored the Topaz and the dredge piles still produce gem stones, though digging and sieving your own patch can prove more rewarding.
Refs.:
http://www.nrm.qld.gov.au/mines/fossicking/pdf/obriens_creek.pdf
http://www.nrm.qld.gov.au/mines/fossicking/designated_lands.html