Topic: Frosted decanter.

[Ekimp]

Might needle work, etched through the resist, produce very fine directional marks?

In reply, reply 13:

I think this was in connection with the grinding decoration on the compote? I think the marks produced by needle etching would be very obvious. Occasionally you see imitations of Northwood’s work where instead of frosting between the needle etched outline with a grinding wheel or white acid frosting (see reply eight), they have used more needle etching. This stands out like a sore thumb and looks very crude and I don’t think something you could mistake for mechanical grinding or proper acid frosting. I can’t find an example at the moment.

My acid etched glass shown below is an example of what I was thinking of re acid etching. Maybe a mod could add the photo to reply 13?

[Ekimp]

This is interesting - an 1861 patent from Charles Bishop, Flint Glass Manufacturer St. Helen’s, Lancaster, for Improvements in Ornamenting Glass [“glass plates and articles of glass”]

https://books.google.co.uk/books?id=bo-0FquxzC4C&pg=RA43-PA3&dq=glass+obscuring+lathe&hl=en&sa=X&ved=2ahUKEwjB0fiQqa_0AhXpQUEAHXwIBoUQ6AF6BAgEEAM#v=onepage&q=glass%20obscuring%20lathe&f=false

He is describing metal stencils so that different areas can be obscured to create patterns but the interesting bit is “...the unprotected portions of the surface of the glass are to be ground by means of wet sand or of emery, applied by a brush wheel composed of wire, and revolving in a lathe or in a glass grinders’ frame in the way that is well known and commonly practised by glass cutters for producing a ground or obscured surface”.

In this case I think the lathe mentioned is just for spinning the brush but it is pretty conclusive proof of the mechanical abrasion method of frosting/obscuring/matting and that it was “commonly practised”.

[flying free]

A good and interesting find.  Thanks. 
I wonder what kind of surface effect was left by the brush. Presumably a  finely striated surface with what looks like very thin fine brush strokes around the body?
( I'm still wondering how the body of my azure blue etruscan style vase was given the satin/matt surface which iirc doesn't have fine lines on the surface)

m

[Ekimp]

I think on the pieces that I have shown, the lines/scratches around the diameter are due to the article being turned whilst the abrasive (possibly a wire brush) was held against it. I have a couple of other items that have uniform looking frosting with no obvious lines or scratches but I am convinced are abraded mechanically. I think like most things, they could probably achieve a wide variety of finishes depending on the quality of the item and how much time was spent.

I have a modern (1980s?) Jon Art object that is acid frosted that I was getting ready to post. The photo below shows a closeup of the finish compared to that on the decanter in this topic. The photos are the same scale with a pin shown for comparison. The mechanical abrasion (on the left), I believe leaves a surface that looks like tiny chips, the acid etched finish looks like very fine condensation with more rounded tiny pits. The antique acid frosting may well look different to this though, but I think it should be noticeably different to the mechanical abrasion.

[flying free]

Great photographs!
I will get some time soon and will do a close up of the blue and a close up of a sand-blasted Japanese cameo piece to show those.
I think the blue close up, from memory, will look like the decanter so perhaps that's how it was done.

[Ekimp]

Thanks. I have a lens that clips over the camera on my tablet and it works surprisingly well for closeups.

It would be interesting to see your examples.

[cagney]

Very, very nice photo's and description. With the contrast of clear glass you really get a feel for the technique. Here are some photo's from an early English creamer probably 1860's.

[Paul S.]

the top down handle looks to confirm your suggestion of approximate date Cagney.       The frosting here lacks any directional appearance, so do we assume this is sand-blasted?     Hajdamach writes that  "the invention of sand-blasting had already taken place by 1870 .................. "   -  invented apparently in the States by one Benjamin C. Tilghman.            What in particular suggests this is English  -  the handle possibly??

[cagney]

See thread Feb.have no ibea18.2018. "Persival, Yates & Vickers creamer ca. 1865"

It has that semi-satin feel of acid treatment. Wether with vapors or brushed or bathed I have no idea. Think it would make a difference? The photo's are a of areas of extreme close up in contrast. As to sandblasted glass I am not familiar with it.

[cagney]

Oops, did not see the typo. Here are some photo's of the whole.