Chalcedony. A semi-precious gemstone named following the nearby town of Chalcedon, and is also offered in a lot of Istanbul's multitude of jewellery shops. These days, most metro stations would not have a staffed ticket booth, so you'll need to get your Istanbulkart in the yellow ticket machines. By tram[edit] https://istanbul-work80123.daneblogger.com/35666052/facts-about-istanbul-work-revealed