I can see it is some sort of needlework but happily this stamp gives lots of other clues, although one at first may wonder where Hrvatska is as most people know it as Croatia. It also gives its date of issue (2010) so a visit to the Universal Postal Union site says it is a set of 4 Croatian Ethnographic Heritage set but nothing else. Looking for that title to tell me more, zilch, I do discover on the first search page that there have been new Ethnographic Museums opened in Dubrovnik and Split, appropriate for a country just a independent republic in 1991. But that still did not help me know what Dubrovacko Primorje was but you always know on the internet there will be an enthusiast on a blog somewhere. I wasn't disappointed because Lina's Land had been taking some embroidery lessons on the stitches of the national costume of this area north west of Dubrovnik and shows some of the beautiful embroidered scarves here.
Well that is one mystery partially solved but there is another that will be for every unknown. The stamp came in a bundle of used stamps on paper from all over the world but this one had been on a postcard, of which now only the small corner with the stamps on remained. Nooooo
A glimpse of an unknown Croatian town
An entry to Viridian Postcard's Sunday Stamp theme of "stamps that leave you wondering"