1923 $1 Large Size Blue Seal Silver Certificate, Signatures of Woods & White FR-238 Grades xf. FR 238. The term “horse blanket” gets used a lot when talking about large size currency. It is most frequently used to describe this bank note. All large size $1 silver certificates have the same blue seal. There are three signature combinations used with 1923 $1 silver certificates. Portrait of George Washington at center.