Aniline is a chemical that is a by product of burning coal. The first synthetic dye (mauve, developed in 1856) was a coal tar product and contained the chemical aniline but the term "aniline" has been used to include other chemical type dyes. Today the term "aniline" is used mainly to differentiate natural dyes from the synthetic dyes. The synthetic dyes offered by The ReRanch do not contain the chemical aniline. Take note that the class of dyes known as aniline are chemicals and as such should be treated with respect. Protective gloves and eyeware is encouraged. Breathing the powered dyes is not! The dyes offered by The ReRanch are the product of Home Stead Finishing. Their web site offers information on using natural dyes as well as the synthetics. The information offered here is how the family of synthetic dyes relates to the builder of wooden instruments. Other products will be discussed in this section that are needed in the preparation of the wood. They are sand paper, oil based grain filler and sand and sealer. The sand paper grades needed for the preparation are grades #180, #220 and #320 with #320 being the finest. All prep sanding should be done using dry sand paper. This will eliminate the risk of introducing moisture into the wood. Grain filler is a thin wood filler like material. The thinner viscosity allows it to penetrate and hold in the grain pits. Normal wood filler will pull out of the grain as it is applied. Grain filler is difficult to find although Wood Craft Stores and other fine wood working stores will carry it. Bartley's is oil based and a good one. It is the one that you will most likely find. (Of course The ReRanch offers a good grade oil based filler as well). Water based fillers are available but have the inherent problem of introducing moisture into the wood. Lastly, sand and sealer is recommended with all woods destined for a perfectly glass-flat glossy finish. Sand and sealer is a high solids content lacquer, vinyl or shellac filler that helps fill the grain but also acts as a leveler for the coats above it. Each product as it is used on a particular wood.">