Dear all, An extensive literature search showed that it was the famous French crystallographer and mineralogist, Renee Haüy, who first described what is now called fluorapophyllite-(K). And that the material he used for his description, came from Sweden. My questions are: ** Is there is an apophyllite specimen in the Haüy collection?* If so, is it from Utö in Sweden? * https://www.mindat.org/loc-226366.html (the spelling on the old labels might slightly differ from the current spelling). If both answers are "yes", then it is very likely we have found the (lost) type specimen for fluorapophyllite-(K) ... I don't know who is "in charge of" the Haüy collection today, hence my message to the whole group. I am willing to share my research with the collection manager if so desired. Cheers, Herwig https://www.mindat.org/user-86.html