Wood is a product of nature – each tree has its own structure and individual colour combination. An image or a sample will therefore never be able to give you a complete picture of the finished floor. Please also note that the colour may change when exposed to light. As a guideline, darker wood species will get a more golden tone, whereas lighter species will become slightly darker. Cracked knots are filled with putty, the occurrence of small gaps between the putty and wood may appear.
Download here the Oak Grading Explanation: