Topic: Frosted decanter.

[Ekimp]

I bought this as I wanted an example of antique acid frosting (and it was very cheap ). I was sure it was going to be acid frosting when looking at it in the shop, but on getting it home and looking through modest magnification, it was apparent that it is another example of mechanical frosting. This has probably been achieved using an abrasive wheel (or possibly a pad) held against the surface while the body was rotated in a lathe of sorts. You can see the striations in the finish from the rotation of the body against an abrasive and also areas where the wheel hasn’t got into the corner at the base - so not sandblasting or acid etching.

I think this method of abrading the surface to create a frosted effect is actually very common (it is in the glass I come across) and maybe on victorian glass it is the norm, rather than the exception.

There is no stopper but there is an etched ‘2’ in the neck. I believe it dates to somewhere in the Victorian period, there is similar Greek key and frosted decoration here: http://www.glassmessages.com/index.php/topic,62608.msg351508.html#msg351508 with discussion on dating of Greek key cutting, Paul S. says Greek key suggests 1860s - 1880s.

[Ekimp]

...two more photos:

[flying free]

nice!  Love the honeycomb cutting on the neck.  It's my favourite type of cut.

m

[Ekimp]

Thanks, I quite like it - if only it had the original stopper!

The frosting makes it look slightly opalescent (if that’s the right term) with the light behind it. I have a goblet with a crackle bowl (similar to one you posted several years ago) but with a frosted stem and foot. The opalescent look is more obvious on that, I wonder if that was partly why they did this frosting. I should imagine with acid frosting, the texture might be more flat and not defuse the light in the same way.

[Paul S.]

did he really - he must have been looking at books again  -  I suspect the Greeks did it too.       There's a lot of glare in the photo, around the neck area, so not easy to see detail  -  might it possibly be scale cutting do you think?

[Ekimp]

Yes, luckily someone else had done the work I think it is scale cutting, hexagonal shaped cuts so honeycomb describes it nicely too...although at the top around the back they ran out of space and they became diamonds. Presumably that lack of symmetry indicates they were cut by hand. Sorry about the photo, had my mind on frosting.

[Paul S.]

I suspect m is correct if the neck cutting shows hexagonal shapes - just that I couldn't see too clearly.      I have a grape washer (so said Pamela a long time back) and the shapes of the grapes and leaves are a matt finish as though by acid, but under the lens these areas show directional lines, so I'd assumed the decoration made by a copper wheel.    I've a large, possibly C19 water jug with extensive areas of matt surface, and under the lens there is an absence of any lines - the surface shows as more granulated than the piece here or my grape washer, so assume that is acid.    I'd could show a picture but the surface detail simply won't show the texture as too great a magnification needed.            Sorry your one has turned out not to be what you wanted  -  give it away and carry on looking for the real thing  -  I don't know how the effect on yours has been achieved  -  could be wrong, but I don't see the bottle spinning on a lather while the guy held some abrasive pad up close, but who knows -  spinning bottles on lathes was a method of adjusting the fit of a stopper 150 years back, but could be risky.   

[flying free]

I wonder if this surface effect is done by brushing acid onto the surface somehow? 
I've no idea if historical accounts show that was how acid was used though 

[Ekimp]

Thanks both, I’ve had a go at convincing people of this abrasive technique of frosting before, (without too much success I think ). https://www.glassmessages.com/index.php/topic,68884.20.html Brushing acid was suggested there (but the brushes would melt).

I can’t see sand blasting or acid etching producing the marks shown on this decanter (or my vases in the other thread above). The area in the corner that I showed on the decanter has been missed, I can’t see that happening if brushing acid, dipping in acid or exposure to acid fumes. I will probably post the goblet I mentioned, I think that has even more clear indications of mechanical frosting.

I wasn’t necessarily thinking of something spinning the glass very fast, it could be spun slowly against a spinning grinding type wheel on a lathe similar to those used to spin the work piece for machine needle acid etching etc (ref Hajdamach page 183, Plate 162)

McConnell 2nd eddition page 80 describes grinding stoppers with various grades of emery using a purpose made lathe as early as 1665, so over 350 years!  A similar technique might work to frost the body of my decanter. Also, on page 284 McConnell quotes John Northwood’s son on how unpleasant it was working with acids “....it was an unpleasant job and no one wanted it. If possible, some used to pay others to do this part for them”. So not much fun using acids either!

Hajdamach on Northwood’s work on pages 184/185 says: “The effects produced by Northwood’s [acid etching] machines consisted only of outlines. If the areas inside the figures were to be shaded the glass was passed to the engraving shop. Broad copper wheels were used to matt [or frost] the surface...” [my square brackets]. He used this mechanical frosting over large areas as illustrated by a jug in Plate 166. He goes on to say Northwood then develops an acid etch frosting treatment used in conjunction with resists, but the grinding method was used by them until c1862.

Also, in Hajdamach page 49, Plate 35 shows a ‘Frosted and Embossed’ vase from Webb Richardson c.1830s. Presumably this would have been frosted with a grinding wheel as it predates Northwood’s development of white acid (for frosting) and sandblasting by a considerable margin.

Keith’s jug here: https://www.glassmessages.com/index.php/topic,70337.msg391649.html might be similar to the jug you mention Paul, as it also looks to have a relatively uniform texture. Sand blasting was another possibility when there were no grinding marks but that wasn’t invented until 1870 and I’m not convinced.

[flying free]

Thank you for taking the time to research the methods and then share them.  Very informative.  Food for thought on my blue opaline vase - need to take a look at it to see if has lines on.

m