The size indication on these products is a little tricky, the measurement given when you choose is the largest measurement, as the product is not completely round but more oval, it is the height that is given when you choose in the list. If you order 10mm, the product is approx. 7mm wide and 11mm high. if you order 19mm, the product is approx. 17mm wide and 19mm high.
316L steel, also known as surgical steel, is the most common material in our jewellery range. It contains about 10-14% nickel but only release less than 0.1 billion gram per cm2 and week. Along with Titanium, this is the most common material in jewellery that we use when we perform a piercing.
Blackline® is black jewelry, they are not "colored" black in the classic sense, it is 316L Steel or Titanium that is covered with a thin plasma film (PVD coating). The thin film is very strong and does not fade. The technology has been used since the late 80's and is used, among other things, for orthopedic implants to provide an extra durable surface.
Blackline® is glossy black and a delight to the eye, they are incredibly beautiful as they are but also really cool if you combine with other colors.