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.

The block is the only known multiple of the 1930 royal wedding test issue

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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