Ἀγεωμέτρητος μηδεὶς εἰσίτω

Gilding and silvering

Gilding makes sundial resistant to weathering and gives the instrument a festive look. A sundial may be gilded as a whole thing. However, we may gild only the gnomon or only the dial. Gold coating never fades and the sundial always looks like new. For gilding I use the method of electrodeposition of gold from a gel solution of its salt. This method provides the most reliable adhesion of gold and substrate material. The thickness of the gold layer is 2-4 microns.

Silver, unlike gold, changes color over time. On the surface of the metal under the influence of atmospheric agents nitrates and sulfates of silver having dark color are formed. In a few years the instrument covered with silver looks older than it really is.