Sometimes Art History throws out a marker so distinct you can make precise date assumptions by it.  If your prized Titian painting has Prussian Blue in it, well bin it, because Prussian Blue wasn’t invented until 1708.  But it works the other way round. Sometimes there are pigments which get ‘forgotten’, and the red spot in this tile from the collection of the Museum of the Order of St John is now apparently ‘forgotten’.

First some background.  This is an Ottoman Fritware tile connected to the Iznik School. It was probably made either in Iznik, Turkey, or an Iznik trained potter may have moved to Damascus or Aleppo and worked and shared his skills to local potters there. Ottoman fritware started out as mostly white and cobalt blue, and was heavily influenced by Chinese blue and white Ming porcelain. Then around the 1520s to 1540s turquoise was introduced, followed by sage green and then a pale aubergine purple. .The blue and sage green colours on this tile are typical of the style favoured in Damascus during this period, but it does appear in the Ottoman Topkapi Palace and other buildings in Istanbul.

Topkapi Palace © Louise Hill-Hottinger

Ottoman fritware started out as mostly white and cobalt blue; yes, Ming- style again.

Then around the 1520s to 1540s turquoise was introduced, followed by sage green and then a pale aubergine purple.

Then a really new thing happened. Bole Red.

Bole red varies in colour between a tomato red and a more orangey version, and it is usually applied in raised texture. And it was seen as rather clever and rather difficult – and its secret formula has been guessed, but never been confirmed.  According to the British Museum, the red pigment came from an iron-rich red earth, or bole, found in Armenia and its application was seen as a technical innovation at the time.  It is known that some of the tile-making workshops in Iznik were owned by Armenians, so there is a plausible connection.

So being new and fashionable (and difficult) of course everyone wanted red bole on their tile for a while,  and this red pigment is associated with the mature classic era of Iznik pottery produced for Istanbul buildings from the 1550s to the 1580s.

But weirdly by the first half of the 1600s no-one knew how to make this colour any more. The potters or glaze makers did not write it down, maybe they were under oath to guard their secret ingredient, like the Venetian glassmakers of Renaissance Murano and the porcelain factory workers in 18^th century Meissen. Exactly when the red died out is in dispute, but it is generally acknowledged to be between the early to mid 17^thcentury, exactly the time when court patronage for ceramic tiles and wares diminished and the Iznik potteries fell on harder times.  And the famous Venetian potters never mastered the Iznik Bole Red either, they had to make do with orange.

So our tile, with its bole red spot, can be dated to be between 1550 to 1580 [ish].  It is the only tile in the museum’s collection with the red, so it may be the only one not made in Damascus, as Damascus tiles are not associated with this red bole pigment.  One thing is for certain, the tile painter knew the red was special, and he would have been bound to secrecy to protect it.  And they succeeded.

Sources:

• https://en.wikipedia.org/wiki/%C4%B0znik_pottery
• http://www.britishmuseum.org/explore/highlights/highlight_objects/me/u/underglaze-painted_tiles.aspx
• The Science and Archaeology of Materials: An Investigation of Inorganic, By Julian Henderson
• http://www.hurriyetdailynews.com/iznik-tile-artists-briefly-paint-the-town-red.aspx?pageID=517&nID=57207&NewsCatID=438