Sophie, all ten of my blocks are unique fabrics. Therefore, my “extra” block really is a donation block. Let me know if you want me to take another picture. I didn’t realize two blocks looked so similar, they don’t in person.
(edited by sophie to include my response)
Laura, the guidelines for the block lotto are that you can enter up to maximum of 9 blocks for a maximum of 9 chances–whether those chances are for yourself or donated to newbies and others who have not yet won. Therefore, your 10th block can be contributed as an extra block to sweeten the pot, but there is no extra chance associated with it and therefore you cannot donate it.