The following is excerpted from Clifford Mishler’s Coins: Questions & Answers
Q: What is the Isabella quarter? How valuable is it?
A: The Isabella quarter, bearing the portrait of Queen Isabella I of Spain, was the second commemorative coin issue of the United States. It was also the first and only 25-cent issue in either the classic or modern commemorative coin series. It must be mentioned for the record, however, that the 1932 Washington quarter was initially intended to be a commemorative, but was continued as a regular issue in 1934, and that the “Drummer Boy” Bicentennial quarter of 1975/76 was produced as a regular issue commemorative.
Pressure upon Congress by Susan B. Anthony and the suffrage movement led to a provision for a coin to benefit the efforts and pay tribute to the participation of the Board of Lady Managers at the Columbian Exposition. Part of the money allotted to them to promote their interest in the exposition was generated from the striking of 40,023 Isabella quarters intended for sale as souvenirs at $1 each. Ultimately, slightly more than 24,000 were issued, with nearly 16,000 being melted following the close of the exposition. Not surprisingly, Isabella quarters command much higher prices than do Columbian halves.