When I went looking for "Fireclay" I was told by a couple of masonary distributors it was the same as "Mortar Clay". Often used as a mortar additive to make standard mortar creamier and stickier. But I was concerned when the 50lbs bag said Mortar Clay and nothing about thermal characteristics. Several of the Forum members have assured me that the two are basicly the same and what they used without any problems.
There is a specialty shop in San Diego called Squires Belt Material Co (4567 Federal Blvd, San Diego, CA - (619) 266-6100) that the other distributors keep referring me to as "the guys who know". They were very helpful and sent me the attached spec sheet for Amador Fireclay made by Ione Minerals Inc.
"Amador airfloated fireclay's plasticity and brightness make it an ideal choice as an addition in the manufacture of stucco and building compound products."
Still doesn't have thermal properties listed but at least it has the right name printed on the bag. 50lbs=$7
There is a specialty shop in San Diego called Squires Belt Material Co (4567 Federal Blvd, San Diego, CA - (619) 266-6100) that the other distributors keep referring me to as "the guys who know". They were very helpful and sent me the attached spec sheet for Amador Fireclay made by Ione Minerals Inc.
"Amador airfloated fireclay's plasticity and brightness make it an ideal choice as an addition in the manufacture of stucco and building compound products."
Still doesn't have thermal properties listed but at least it has the right name printed on the bag. 50lbs=$7
Comment