Why this place has aquired the name "Brea Stamps" is a mystery to me, It was and still is known by the name it traded under, "Brea Tin Streams".
There was never any stamps on this site, at least not in connection with any of the remains that are there today.
There were three sets of stamps in Brea and none of them bore the name of the village! all of them being named after their owners.
Going back to the site in question.
Any reduction in pulp size was achieved by a pebble mill not stamps, the feed for these streams coming from Gwithian in the form of tin bearing beach sand. sand would also been aquired from the Red River.
The pebbles for the mill were collected from the beach at Porthpean near St. Austell, South Crofty also sent a lorry up there for the same reason.
The round structures in the photo are not buddles but "Linkenbach stationary slime tables". These were very popular in the tinstreams along the Red River as they could be operated around the clock without any attention. To the best of my knowledge these tables were not used anywhere else in Cornwall, but I stand to be corrected on this.
A discription of the way they worked can be found in "Machinery for Metalliferous Mines", by Davies