Stains are used to give wood another colour without masking the structure of the wood substrate. They can consist of binders, dyes, micro pigments finely dispersed in water or solvents. During the staining process, the more porous portions of the wood absorb more stain, creating a reversed stain image. Nowadays, we also have stains that can neutralise this effect and actually produce a positive stain image. It is important to note that when staining, fine sanding of the substrate is crucial to the end result. Furthermore the colour can vary considerably depending on the size of the grain and type of sandpaper used and thus tests should be conducted before application to check and determine colour and appearance of the stained product.