Color Variations in Wilkeson Sandstone
Remember, this stone was originally the bottom of a river, so the variation in color is extremely unpredictable. There is also a fair amount of coal present in the stone which adds to the unpredictability. We can only guess at what the inside of a piece of stone will look like and never really know until the piece is cut and broken down. Having said that, you can fairly accurately describe color variations of Wilkeson Sandstone using the following terms:
"Silver Grey"
Refers to monochromatic pieces with minimal color variations. Bands of darker grey are not uncommon, and in some cases are the only distinguishing characteristics from concrete.
"Cinnamon" or "Cinnamon Swirl"
Most pieces have some amount of cinnamon or rust color swirled or rifted through them. The pattern and figure of the stone will depend on how the stone is cut with respect to the grain pattern. A perpendicular cut will yield pieces with relatively straight banding, while cutting parallel to the grain will tend to yield pieces with a swirling pattern. Unless directed otherwise, we will usually try to cut with the grain to yield stronger pieces.
"Silver with color"
"Silver with Color" refers to pieces with orange and brown color that has weeped into the stone over time. It is usually banded around the edge in varying thicknesses depending on development conditions.
"Full color" 
"Full Color" is a piece that has been fully saturated with the orange and brown color spectrum in a swirling pattern. The compressive strength of "full color" stone is typically less than "silver grey", i.e. it will fall apart easier. Well bonded "full color" pieces are hard to come by thus a premium is paid for such stone. Availability is limited!
"Oatmeal"
"Oatmeal" color has a light brown / tan tint and is usually coarser grained than the silver grey.
“Feather Coal” is depicted in this last picture and can run through all color types. Most of the time it is not known whether or not a piece will have feather coal in it until it is sawn. Some people refer to this as “pencil coal” because of it’s similarity to small lines drawn with a pencil. Specify if feather coal is unacceptable and please note that tight restrictions on color will affect price and timeline.
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