Topic: Stylish Jade Green Uranium Glass Vase Frosted Outside

[Lustrousstone]

It's the time factor. Acid takes minutes, mechanical means would take much, much longer. These were made in factories by workers on piece rates or at least targets

[Ekimp]

I do get that...but I think mechanical abrasion could take seconds, not minutes, especially with skilled operators and if the machines were setup for production...plus it fits with the observation of the finish on my vases which doesn’t seem to be explained by acid etching.

[BlueOctopus]

Be gentle if I missed something in between. But a acid dip will be the last finish, and if then the stand will be frosted as well, on the first pictures the stand seems quite clear, so I think it is a mechanical method. May be sand blast, may be weel...

[Ekimp]

Hi Monik  yes, that is one of the reasons I thought mechanical. Any area that was not frosted would need to be masked off wouldn’t it. Such as on KevinH’s example, why would they bother masking under the rim.

Edited to add that KevinH said his looks acid etched, which I wasn’t doubting in his example in his hands, just it seemed peculiar and seemed to tie in with observations of my vases.

[KevinH]

Such as on KevinH’s example, why would they bother masking under the rim.

A mask would only be needed if some sort of decorative motif was required within the acid finished parts.

Use of a brush to apply the acid would be the easiest way to "frost" my vase and leave clear glass for the underside of the foot, the underside of the rim, and above the rim towards the inner part of the body.

But I am open minded about this. 

[Lustrousstone]

It wasn't an acid dip (I can't think of any old frosted glass that is frosted on all surfaces); it was brushed on by hand with masking if required for the design. It is also likely that any grinding equipment wasn't equipped for large surface areas much beyond a pontil mark area and might not even have been electrical. (Your cutting and engraving equipment would have just been for that.) These were 19th century glass companies not engineering companies (any engineering would be restricted to the mould making shop and maintenance) and a man (though probably a lady) with a pot and a brush is a quick cheap option.

[BlueOctopus]

The acid which is used to frost glass is HF sorry I don‘t know the English word for that. But this is the most potent acid in the world, and nearly no material is able to stand it. To put the acid by brush will mean to have a big risk with drops and so on. To dip it into a beaker or something similar makes it much more easy.

What ever... a nice vase
Monika

[Lustrousstone]

Hydrofluoric acid - yes it's very nasty but this was the 19th century

[Ekimp]

What did they make the brushes out of?

[BlueOctopus]

The only material that stands HF is plastic. The acid is stored in plastic flasks as well. Please don‘t ask me which material they used before plastic age, maybe some metal. Gold could maybe work. So I think the brushes are out of plastic. HF is still in use in the glass   industry.

Really nasty
Monika