Interesting Footnote on this

 On Sept 29, 1930 this was part of  a 15 stamp series paying tribute to Christopher Columbus which was privately produced and presented to the Spanish Postal Authority which placed them on sale and allowed them to be used for 3 days and keeping the revenue from the sales. I'd certainly be interested in gleaning more info on this set. # 429 in my catalogue of the set #418-432.

JimmyB