Adding a Reference to a Library class in VB Net (Foundation)

I have added a reference to System.Drawing in my library class and it will now accept a System.Drawing.Point object in my code, but it will not accept a System.Drawing.Color object, nor can I find another place that I might need to add to my References. When I do this I get a BC30002 - Type System.Drawing.Color is not defined error. How do I deal with this error? Thanks.