Considered the most natural, dyed in the tanning process and sealed with natural oils and/or waxes but without any corrective or additional protection finishing. This 'full grain' leather retains more character, is the most supple with a natural scent, grainy aesthetic and non-uniform appearance. Only leather hides with the very fewest marks and scars are selected and so more expensive.
Tanned and then top-coated to provide protection against staining and improve wear resilience. The top coat can lighten when stretched referred to as 'pull-up leather' (patina). The 'top grain' light sanding process minimally alters the surface to minimise hide imperfections. Some suppliers may also emboss this leather to improve the grain presentation.
These hides are sanded down to remove natural marks, defects and scars and then embossed to reinstate the surface appearance and texture. It's then given a plastic (clear sealant polymer) coating, permeable enough to allow the leather to breathe, yet enough to slow the absorption of liquids and substances. Considered less natural but most durable.