This is how roasted coffee is transformed from green (raw) to brown (roasted). Also notice how the beans almost double in size. Top left is green coffee, bottom left is a light roast and bottom right is where dark roast would start. Because this roast was stopped at the beginning of a dark roast the surface oil will only start to show up a week or two later.
![](http://cdn.shopify.com/s/files/1/0689/5839/files/1_1024x1024.jpg?v=1474657499)