Sable Crested Geckos
As a crested gecko grows, the Sable gene pulls out the orange and yellow while piling on white. This results in a tricolour hatchling that ends up near black, brown or grey with frosted crests. Because the look keeps building with age, judge one by its head and the white across its back.
About the Sable gene
The Sable gene for crested geckos pushes the pattern towards heavy white. It strips out the yellow and orange as the animal matures. You get a gecko that is grey, brown or near-black with thick white patches over the back and white crests.
Appearance
The head should be your first focus. The crests are outlined in white and the head often has white spotting and a muted headstamp. There are thick white patches on the dorsum with few breaks, and a line down the centre of the back is seen on some animals. The base colour ranges from light grey to brown and nearly black. A tricolour look is more common for hatchlings which show little white. White spreads quickly from the dorsum into the upper laterals as they grow. The white spotting grows into high white, which is a different thing from snowflake. The yellow and orange tones are subdued as the lateral colour fades to a greyish tan. Because of this, a young Sable undersells the adult it becomes. Super Sable looks unlike both a Sable and a Super Cappuccino.
Genetics
Many in the hobby call Sable "co-dom", though it is incomplete dominant. A single copy results in the Sable look, while two copies produce Super Sable. This gene shares a locus with Cappuccino. An animal with one copy of each is called a Luwak. The gene came from Cindy McDannell at Gecko Haven. Her male Rialto, born in 2017, was the first Sable.