A block of four 1930 Italian royal wedding stamps is set to lead Spink's Philatelic Collector's Series sale in Geneva on January 30 with a $117,889 estimate.
The lot is part of a test series printed with a green background, in contrast to the official issue which was printed in orange.
It's the only known multiple of this rare stamp, drawn from a single sheet of 50, and is likely to inspire frenzied bidding as a result.
A cover displaying a fractioned Italian 1850 30c dark brown is estimated at $88,417.
Fractioning allowed one single stamp to be used on multiple letters. In this case, the 30c has been split in half - reducing its value to 15c.
The practice was uncommon. The present lot is one of only three surviving fractional covers from the Lomardy-Venetia region - justifying its high value.
Also on offer is an 1859 mixed franking cover displaying two 20c Azzurro provisional government stamps alongside a Sardinian 5c pale olive. It could make $70,733.
The high number of frankings and cancels makes this a highly desirable rarity.
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