I use both red deer (farm grown) and sambar (indian source) and find significant differences in surface texture, colour, and thickness.
Red deer tend to exhibit a pebbly surface texture while sambar has a more grooved surface with out the pebbles.
Red deer have a bright white colour in the outer shell while the Sambar is a little darker, more creamy).
The red deer that I use tends to be thinner than the sambar but that could be attributed to growing season and temperature. I not really sure.
George