Varnish is composed of clay minerals, oxides and hydroxides of manganese and/or iron, as well as other particles such as sand grains and trace elements.
(Varnish; is composed; of clay minerals, oxides and hydroxides of manganese and/or iron, as well as other particles such as sand grains and trace elements)
Varnish
is composed
of clay minerals, oxides and hydroxides of manganese and/or iron, as well as other particles such as sand grains and trace elements