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YOU ARE HERE:>>REAL or FAKE>Fake classical pottery>section 3, page 3
Someone asked me about this piece bought on a UK antiquities auction website.
Gnathia Ware knot handled olpe purchased from online auction website September 2015. 110mm
The general form is correct although the piece is rather smaller than most examples of this type. Knot handle quite close to the lip. (Generally speaking knot handles are further away from the upper attachment of the handle than in this piece). Vertically ribbed body. Pedestal base with reserved area above base. Painting in white, yellow and red ochre - is relatively poorly done. Plain band of red ochre at top of ribbing. This forms a half square beneath the handle attachment and then meets up with the line on the other side in a some what clumsy fashion. On neck a simple thin yellow/white band with pellet dots below and above, with a larger dot to the front Badly repaired chip on lip.
Basic tests. None are definitive, only suggestive.
Smell when moistened is 'fresh' not 'musty' as many (but not all) ancient terracotta artefacts are. (An area not treated with any solvents as above should be odor tested.)
Weight - This piece weighs 169 grams - unusually heavy for the size. Ancient classical pottery is almost invariably lighter in weight than similarly sized modern pieces. I would have expected this piece if genuinely ancient to weigh no more than 130 grams.
Resonance when tapping with a metal implement is high pitched not dull. This suggests modern firing at very high temperature. This dull resonance is found in most terracotta vessels fired in antiquity. The firing process in the kilns used the time such pottery was made achieved a temperature higher than 900 degrees C (which is of course needed to vitrify the clay particles) but probably not higher than 1050 degrees C Modern electric and gas fired kilns are used normally in the range of 1200 to 1400 degrees C.
Black 'glaze' is very even and uniform : genuine glazes/fired slips show some variation. There is crackling on parts of which looks like crackling of paint not the loss of fired slip.
From Nick: I would also add that this variation in glaze is rather easy to spot in most instances if one looks closely and in bright light. Sort of a patchy variation in the lustrousness of the glaze, and has a sort of blue and occasionally golden iridescence at times. But there is one regional glaze where this variation is a tad harder to spot: the sometimes more matt, inferior Campanian glaze. It is nonetheless there if one looks very closely
Painted polychrome details Gnathia ware is characterized by polychrome motifs and patterns created by applying purple-red, yellow, and white directly on top of the black gloss (slip) before the vessels were fired. Such painted colours are therefore generally rendered rather 'flat' in consequence of these added colours undergoing the entire firing process. Whereas the white/yellow painted decoration is flat, the red ochre band is noticeably raised. It very much appears to have been added to the fired pottery at the very end of the entire manufacturing process and looks like fairly recently painted decoration. Fixity of colours - acetone test
Black coloured areas easily come off with acetone. This will never occur with a fired slip. Sometimes ancient black glazed pieces are 'improved' by using black shoe polish and acetone will to some extent remove this as well.
However, very tiny bits of red and white/yellow painted areas also easily lifted off with acetone which makes it rather likely that the black colour lifted off is also actually new paint and not black shoe polish.
Absolutely clean : no genuine encrustations, sandy or lime accretions. Not even isolated grains of sand seen under the binocular microscope.
There was a very fine and evenly dispersed, as if 'sprayed' on, altogether false looking surface 'accretion'. Nothing like the uneven and patchy and variegated accretions one does sometimes find. What one can see is uniformly spread, non granular and of only one type. And there was similar inside the piece as well: similarly as if sprayed in.
Absolutely no trace of roots marks.( Of course by no means all ancient pottery has roots marks )
X-Ray fluorescence: I haven't actually had XRF done on these ( the above are 'mock-ups') but one would expect to find iron in the black coloured area if genuine fired slip but not if coloured with modern ceramic paint or black shoe polish which contains carbon black or 'lampblack' (carbon particles) and or an azo or nigrosine dye none of which contain any iron.
Thermoluminescence (TL) dating to determine when the pottery was last fired.
Neither is worth doing in this case. Many fakes of Gnathia Ware on the market. Many actually have fake accretions and the surfaces are artificially aged more than has been attempted with this piece. (These photos from a very important book: contact me for details if you want to know where to buy a copy.) |
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