Handmade Antique
Mica
Mica marbles are pontil-era German handmade marbles with flakes of mineral mica suspended in the glass — tilt one under a lamp and it throws back a silver flash. They sit inside several families (onionskin mica, clambroth mica, end of day mica), and the construction underneath still comes first.
What to look for
- Density and even spread of the flakes drive the price.
- Coloured-base mica is scarcer than clear-base.
- Onionskin mica and end of day mica are the names collectors search most.
- Photograph moving light across the surface to show the flash.
Collector notes
The flash is the whole game with mica. A marble with sparse, patchy flakes reads flat in hand even when the base glass is pretty; a dense, even spread lights up from across the room. We grade the glass the same way as any other marble — the mica itself is an inclusion, so its coverage is a quality note, not a condition issue. Two ground pontils are expected on genuine handmade examples and are manufacturing marks, never damage. If you are building a mica shelf, mix constructions: an onionskin mica next to a clambroth mica shows off the range better than two of the same.