Waterglass is sodium silicate dissolved in water that upon drying forms soda glass. Could it therefore be used to cast a glass object like a slab or will it not form nicely?
https://en.wikipedia.org/wiki/Sodium_silicate#Crystal_gardens said:Crystal gardens
When crystals of a number of metallic salts are dropped into a solution of water glass, simple or branching stalagmites of coloured metal silicates are formed. This phenomenon has been used by manufacturers of toys and chemistry sets to provide instructive enjoyment to many generations of children from the early 20th century until the present. An early mention of crystals of metallic salts forming a "chemical garden" in sodium silicate is found in the 1946 Modern Mechanix magazine. Metal salts used included the sulfates and/or chlorides of copper, cobalt, iron, nickel, and manganese.
Sodium silicate is used as a deflocculant in casting slips helping reduce viscosity and the need for large amounts of water to liquidize the clay body. It is also used to create a crackle effect in pottery, usually wheel-thrown. A vase or bottle is thrown on the wheel, fairly narrow and with thick walls. Sodium silicate is brushed on a section of the piece. After 5 minutes, the wall of the piece is stretched outward with a rib or hand. The result is a wrinkled or cracked look.
It is also the main agent in "magic water", which is used when joining clay pieces, especially if the moisture level of the two differs.
A) Be careful in pouring into mold to not mix air in the liquid... as in pour gentle down the side of the moldHow you get the bubbles out remains beyond me...