What type of covering,once often used on scientific instrument cases, is called 'Shagreen'?
Shagreen or if the technique was developed separately. In the 17th and early 18th centuries, the term "shagreen" began to be applied to leather made from sharkskin or the skin of a rayfish (probably the pearled ray, "Hypolophus sephen"). This form is also termed sharkskin or galuchat. Such skins are naturally covered with round, closely set, calcified papillae called placoid scales, whose size is chiefly dependent on the age and size of the animal. These scales are ground down to give a roughened surface of rounded pale protrusions, between which the dye (again, typically green vegetable dye) shows when the material
Shagreen of its introduction from China perhaps during the 16th century rule of Suleiman the Magnificent. Three items made of shagreen can be found in the Topkapi collection. Since the 18th century Shagreen has typically been used for covering portable items such as luggage, toilet cases and other boxes, the hard and robust looking finish seeming to assure its reputation for standing up to rough handling; book coverings are also known as well as larger pieces of furniture. The water resistant qualities ascribed to the finish are probably why there are many toiletry cases and associated objects such as shaving kits,