The main visual feature of the selenite tile is long mineral bands and changes in transparency across the broad face, framed by a tile form. The stated 20cm measurement is a guide for the tile rather than a millimetre-exact figure.Useful details Material: Selenite Colour: White Approximate size: 20cm Finish: Polished surface Design: Tile form Rather than moving it regularly, leave the tile on a lined shelf away from keys and coins so corners do not project into a busy area. The piece can also be displayed on its own instead of being used beneath another ornament. Move it by supporting the broad underside rather than pinching a single edge. Do not attach adhesive pads to the stone face; the broad surface and edges can still be marked by pressure or moisture.Variation between pieces: Natural selenite is not uniform, and on the tile this is most noticeable in the way the thickness changes along the outline. Differences in cloudiness, colour and transparency are expected across examples of the tile.A little care: A gentle dry clean is enough for the tile: hold two sides while cleaning the top surface; dry dusting is preferable to occasional heavy cleaning. A settled display is best, so leave the tile with the broad face left uncovered without wrapping the stone in anything wet or abrasive. Delivery Information Your crystal will be on its way soon. Orders normally leave us within a couple of days. Most arrive around 3 working days later.