Agate Burnisher: a Polished Agate Tongue in a Beech Handle

Water-gilded gold leaf, once dry, is burnished to a bright shine with a piece of polished agate. Agate is mostly chalcedony and very hard. Grind a small piece of agate to a smooth, curved tongue on sandstone with emery, polish it through finer and finer grits to a mirror, and set it in a copper ferrule on a beech handle. The picture: a gilded frame being burnished with a curved agate tool.