Natural Rubber is normally Abbreviated to NR and is rubber obtained from the latex of the rubber tree. Rubber sheeting that purports to be Natural Rubber should be manufactured as a blend of a number of materials including a percentage of Natural Rubber. High Grade Natural Rubbers typically used in Abrasive Resistant Applications normally include high levels of Natural Rubber, however in todays markets a lot of low grade solid rubber "commercial products" are mixed with SBR (Styrene Butadiene Rubber) a lower performing synthetic polymer to produce a Rubber Sheeting that is often fit for function.
Food Grade Rubber in Natural Rubber is typically manufactured as White Rubber and should be independently tested and certified to EU1935 or FDA. MacLellan Food Quality Rubber is also certified Nitrosamine Free.