SweetPeaWilly

What should i use then? Online sources all use Portland. Should i just do 50/50 with the clay and sand?

Hey, i'm planning on making a small foundry for aluminum, I plan on using a mixture of Fire mortarclay, portland cement, and silica sand. Can anyone suggest a ratio and amount of water i should use. 

I want to use it to melt low tempurate metals, like aluminum and tin, but I also want to use it to temper and fold steel for swords and knifes. 

Hey, I'm new to the world of smelting, I'm going to turn an my useless 23'' Weber BBQ into a Foundry. My question is, what should my refractory solution be? I have a 50lbs bag of Mortar Fire Clay. I look online, and i can not find silica sand. perlite also seems really expensive. I'm looking for any suggestions, as I could us it graciously.