Vermiculite?

[meco211]

I am currently building an oven, and not sure if i have the right insulation. i had went to our local concrete / masonry supplier and told them that i need some bags of Vermiculite and they sold me a product called Zonolite. They said that it is the same stuff. But everything i have read shows vermiculite in a more porous form and this stuff is a very fine powder that almost reminds me of pepper. It says that it is used for pouring into block walls as insulation. I attempted to mix a sample of 5 to 1 with Portland cement and will see how it turns out in the morning, but i am worried that i might not have the right stuff?

[meco211]

Well i checked it this morning and it is kinda hard, but not solid like concrete! but i think i have found vermiculite at our local building supplier