Talc is used for many applications in woodworking. From making gesso to be used as a decorative finish or as a grain filler, etc. to use as a lubricant and fine abrasive, this is a versatile product, with uses that are only limited by your imagination. Gesso is a mixture of glue and talcum powder or calcium carbonate and is used as a base for other finishes, notably gold leaf. When dry, the gesso is extremely hard and durable. It can be sanded to give a silky smooth finish and burnished to produce a shine.