This is classic material from the Epprechtstein, a granite mountain with pegmatites in the northern Bavarian Fichtelgebirge. Unfortunately, the specimen comes without a more precise locality, but it is a very nice cluster of well-formed, sharp Orthoclase crystals. A twin plane is visible on at least one of the crystals, which are abundantly coated with sparkling olive-yellow Gilbertite micro crystals. An all around pristine specimens which can displayed from every angle. Wikipedia claims that the Epprechtein “is mineralogically the most interesting mountain in the entire Fichtelgebirge upland range” where (depending on the source) 15 to 20 quarries operated to mine the granite and the pegmatites. Mindat knows that all quarries are abandoned except three quarries where granite is mined.