Guitar shellac flakes available in : SuperBlonde dewaxed shellac, Lemon 1st and pumice
Shellac are a resin produced by insects that live on the branches of some trees in India, the raw shellac is collected from the tree and crushed and proceed to its selection, then heated, compressed and transformed into a plastic mass ready to extend it, forming thin sheets and allowed to dry for subsequent cutting, which is how we find it in the market.
Shellac is hard and resistant, and offers a good covering quality, its thin film has a high gloss that is resistant to abrasion and deterioration from UV rays.
This product is soluble in alcohol, insoluble in water and slightly soluble in acetone and ether.
Pumice is an igneous or volcanic rock in powder form, it contains silicon oxide and aluminum oxide, it generates a very fine powder that is used for various finishing techniques.
Obtained from high purity silicate stones, it is especially valued as a filler in French polish finishes.
In spite of its opaque coloration, the mixture of this powder with shellac produces a transparent finishing paste.
Its use as a filler, mixed with alcohol and in some cases some oil, for filling pores seeks to obtain a smooth surface on which the final finish is easy to apply. It can also be mixed with water or liquid kerosene for other types of finishes.
The purpose of the shellac finish is to protect the wood by closing the pores and giving it hardness and elasticity.
You can see a practical tutorial on how to apply shellac.
There is also a tutorial on how to make shellac and its preparation.