Chalcedony. A semi-treasured gemstone named following the close by city of Chalcedon, and it is sold in a lot of Istanbul's large number of jewellery retailers. Currently, most metro stations do not have a staffed ticket booth, so you will need to receive your Istanbulkart from the yellow ticket equipment. https://istanbul-wordpress68901.tkzblog.com/36504518/5-essential-elements-for-istanbul-wordpress