There are currently 6 glossaries in this directory beginning with the letter O.
Op Art or Optical Art
An abstract art that uses precise, hard-edged patterns in strong colours and make the images appear to move.
Opal
This gemstone is believed to reflect the colors of all other gemstones. Opal is the birthstone for October and the traditional gift for the 14th wedding anniversary.
Open back setting - a setting in which the back of the stone can be seen.Palette
The surface on which a painter will mix his colours. Also the range of colours used by an artist.