Buff is used as a catch-all term in the UK and US for non-agouti rats with the red eye dilute gene, but the actual show standard for buff refers to a warm magnolia colour (think magnolia paint, rather than the magnolia flower) The eyes at first glance often look black, but they’re actually a very dark ruby color.
When we refer to the variety of Buff coloring in our rats, we are speaking about our mink colored rats with the red eye dilute. Most commonly we get buff rats in our odd eye mink line. When born they look almost white but they actually have a slight tint of tan or gray. There eye colors usually range from red, ruby or odd eye.