I see the Library of Virginia has added the certificates and affidavits of freedom for Albemarle County to their on-line African American Narrative on VirginiaMemory.com.
Several interesting affidavits were for the children of James and Rebecca Going who were given certificates of freedom based on "Indian decent" in 1833.
Joshua D. Rothman in his book "Notorious in the Neighborhood, Sex and Families across the Color Line in Virginia" explains that in 1832 the General Assembly passed a law which imposed severe restrictions on free people of color. In March 1833 they passed another law to provide an exception for those who were neither white nor considered people of color, classified as "Indian" [pp. 210-211].
There are many such registrations for light-skinned families associated with the Bass family in Norfolk County after March 1833: Bass, Newton, Hall, Flora, Perkins, Price and Weaver.
This is the first I've seen outside of Norfolk County, but I don't always check registrations after 1830.
Before 1833 such people were usually registered as "bright mulattos." There were six Goings households counted as "free colored" in the Albemarle County census in 1840 with white wives.
It's interesting that dark-skinned families like the Colemans who were freed based on descent from an Indian mother did not receive such certificates.