I occasionally find octagonal caisse cancels, such as this one from Arsdorf dated August 11, 1971, on documents – in this instance, on a deposit receipt.
I would be interested in learning more about the uses of the caisse cancels. In particular, why were they used instead of the office’s regular postal cancel for documents such as the one shown here? Could a postal cancel have been used instead? Were these cancels ever used to cancel stamps? When were the first introduced? Were they issued to all post offices?
On this deposit receipt above, the Arsdorf double-circle postal cancel dated October 28, 1935, is seen.
Update – August 8, 2011
These cancels and their cousins are no longer a mystery! The FSPL’s Commission d’Études in March 2011 published a comprehensive study and listing of these cancels as chapter 8 of the Handbuch zur Philatelie in Luxemburg.
The Handbuch illustrates the various types of octagonal kassenstempel, as shown below.
Thanks to the dedicated work of the FSPL, I now better understand and appreciate my Arsdorf caisse cancel! It was one of those philatelic mysteries that I thought might never be solved.