The listing, 1930's Martha Washington stamp has ended.
I believe this stamp to be from the 1938 set
The famous Presidential Issue, known as "Prexies" for short, came out in 1938. The series featured all 29 U.S. presidents through Calvin Coolidge, each of whom appeared in profile as a small sculptural bust. Values of 50¢ and lower were mono-colored; on the $1, $2, and $5 stamps the presidents' images were printed in black on white, surrounded by colored lettering and ornamentation. Up through the 22¢ Cleveland stamp, the denomination assigned to each president corresponds to his position in the presidential roster: thus the first president, Washington, is on the 1¢ value, the seventeenth, Andrew Johnson, is on the 17¢ value, etc. Additional stamps depict Franklin (½¢), Martha Washington (1½¢), and the White House (4½¢). Many of the values were included merely to place the presidents in proper numerical order and did not necessarily correspond to a postal rate; and one of the (difficult) games for Prexie collectors is to find a cover with, for instance, a single 16¢ stamp that pays a combination of rate and fees valid during the Prexies' period of usage. Many such covers remain to be discovered; some sellers on eBay have been surprised to discover an ordinary-seeming cover bid up to several hundred dollars because it was one of the sought-after solo usages. The Presidential issue remained in distribution for many years. Not until 1954 did the Post Office begin replacing its values with the stamps of a new definitive issue, the Liberty series.
I am not a stamp appraiser so please feel free to ask questions.
Paypal only and I combine shipping.