Thanks to Nureddin Gürpinar for the image of his Ottoman coin card. The coin on it looks like a 5 piastre piece but it's not the same variety as the one on the H.S.M. Ottoman era card shown here.

From the initials on the back, he identified the maker of his card as Brüder Kohn of Vienna (B.K. (space) W.I.). The W.I. must stand for Wien, district I. Haven't seen that imprint before. H.S.M. stands for Hugo Semmler, Magdeburg.

As you see, the Semmler card was sent from Constantinople-Galata Francaise on 1 December 1909, with a 10 centimes French Levant postage stamp, to Paris where it was received on 4 December 1909. (In those days, postmarks were stamped at the receiving post office as well as the sending one.) On the back is the sender's ink stamp with an ID that translates as "son of the Marshal Hairi Pacha." Don't know what a "major détat-major" is – perhaps a French diplomat? There's also an ink stamp in Arabic – can one of our readers translate it?

Love these coin cards, especially those that were postally used.