Guess the Date

Mercury Glass vase 1I make no claims to expertise in any class of antiques whatever.  Not enough focus, not enough application, not sufficiently single-minded.  But I do like to think that I’m quite good at dating things.  This is not a rare skill.  Any dealer or auctioneer and most antiques buffs can do it too. Once you’ve looked at many antiques over many years, you can tell pretty accurately for most commonly-encountered objects the likely year when they were made.  When I say accurately, I mean within a couple of decades either side, which is normally good enough.

Take a mahogany chair, for example. It’s easy to tell after some practice whether it is early or late Georgian, Regency, William IV, early, mid- or late Victorian, Edwardian, or a later reproduction.  You look at the style, the wood, the patina, you feel the weight, and you know.

I’m fairly confident about being able to date many types of antique object made in the last 200-300 years – furniture, ceramics, glass, pictures, clocks, carpets and rugs, and so on and on. Or at least, I was until yesterday, when I received a severe blow to my confidence.

There I was, in a large Edinburgh charity shop where I’ve had several good finds, with limited time because of parking wardens on the prowl outside, and inside, shelf after shelf and table after table of – well, yesterday it was almost uniformly garbage.

Only one object stood out – but solely because of its extreme blinginess and total vulgarity.  A trumpet-mouthed vase with a knop stem, about 9 inches tall, in the brightest, shiniest, most luminous lime-green that you’ve ever seen in your life. Plastic? I picked it up. No, it was cold to the touch.  Must be glass.  It was thick-walled and fat, but not sufficiently heavy to be solid glass. Got it! It must be a vacuum flask-type construction like the liner inside the old-fashioned Thermos flasks that we used to take on picnics to keep the soup hot. I didn’t know they made vases like that, and I didn’t know they made them in any other colour than bright silver, but it couldn’t really be anything else.

For confirmation, I picked it up and looked at its underside.  Sure enough, it must be double-walled.  In the centre of the base was a small circular metal plate, apparently inserted in the glass to seal the vacuum.  On the plate was impressed the words E VARNISH & Co PATENT LONDON.  Meant nothing to me.  Presumably a Thermos knock-off.  With its slight art-deco look, its minimalist lines and its zingy green colour, it must date from a little before the last war or perhaps shortly after.  Confidently in the range 1930-1950.  Its picture is above.  Judge for yourself.Mercury Glass vase 9

I put the vase down again. Not my type of thing at all. No possible interest or value. Then I picked it up again, don’t know why. Went to the counter, paid the three quid on the price label, left the shop.  Got back to the car: no wardens. Came home.  Looked up E VARNISH & Co on Google.

And got a shock.  It’s not twentieth century at all. The patent referred to on the sealing plate was for a technique to produce double-walled glass forms for silvering on the inside. It was granted jointly to Edward Varnish and his partner Frederick Hale Thomson in 1849. They were glass dealers and retailers, and glassware using their patent was made for them by James Powell’s famous Whitefriars Glassworks in London.  In 1851 they attracted lots of attention by taking a stand at the Great Exhibition in London to show off their new products, which they called “Mercury Glass”.  But because it was difficult and expensive to produce, they stopped production in 1855.  You can read all about it in this very interesting article: http://www.antiquemercuryglass.com/files/English_Silvered_Mercury_Glass.pdf.

If you google images of Mercury Glass, you get lots of pictures of new products which are – er, cheap modern kitsch, and you get lots of pictures of old products which are – er, cheap Victorian kitsch.  This is because a huge amount of cheap mercury glass was produced in Bohemia in the later nineteenth century for mass markets, usually decorated according to a florid and exuberant Germanic taste.

But you see very few pictures of Varnish Patent mercury glass, and this is because, having been made for only six years, and being rather fragile and prone to deterioration if the seal is broken, it’s extremely rare.  Of the few pictures that you do see, scarcely any are in the glowing green colour.  They tend to be in plain or etched clear glass with the silver inner coating, or else cased with an additional glass layer in another colour (usually a sober red or blue), and etched or wheel-cut with typical Victorian decorations.  I was able to find only a couple of other online images of green examples.

So it appears that my vase is a rarity among rarities.  Which is gratifying in itself, but there’s still the issue of it having been made between 1849 and 1855, and not between 1930 and 1950 as I had estimated.  That really is a bit embarrassing in view of my self-proclaimed prowess for accurate dating.

I reckon it was the luminous greenness that misled me.  There’s something so totally in-your-face and non-Victorian about it. It just had to be mid-twentieth century.

But on further reading I found out that this loud, zingy colour was in fact quite fashionable from time to time during the nineteenth century.  It was normally made by adding an oxide of uranium to the glass, producing very bright monochrome green or yellow wares earlier on, and later in the century being refined to make Vaseline glass, which had much more subtle colour effects.  uranium glassAs you can see from this picture (found here), Victorian uranium glass, although brightly coloured, tends to look very Victorian in style – most unlike my minimalist vase with its curvaceous lines and absence of decoration.

Uranium glass is radioactive, and, not having a Geiger counter to hand, I can’t verify whether my vase is indeed made from this type of glass.  On the whole I think not, because uranium glass glows with a weird luminosity under ultra-violet light and my vase does not.  There were other recipes in existence for making green glass, and I think it likely that my vase was made without uranium, deriving its uranium-type brightness only from being silvered inside.

Whatever may be the truth, the result is an object which very decidedly has a non-Victorian appearance, but was undoubtedly made very close to the middle of the nineteenth century.

I sent some pictures of the vase to Diane Lytwyn, a collector and dealer in mercury glass from  Massachusetts.  Her informative website is here. She replied enthusiastically, providing a tentative valuation of US$500. A perfect piece of Random Treasure, and a fantastic opportunity to learn about something which was entirely new to me.

I ’ll probably sell the vase, because, as you can see below, it really doesn’t fit in with my usual slightly more austere tastes.Mercury Glass vase 10.jpg


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