Chalcedony. A semi-cherished gemstone named after the nearby city of Chalcedon, and is offered in a lot of Istanbul's multitude of jewellery outlets. These days, most metro stations would not have a staffed ticket booth, so you will have to get hold of your Istanbulkart with the yellow ticket devices. https://istanbulwp46789.shopping-wiki.com/9363856/indicators_on_istanbul_work_you_should_know