Determination of age

Even the kind of the centre motif and the design of the corner motifs can give some indications to the age of a tile,  

you have to consider that the patterns were used for several centuries.  

Two landscape tiles with similar motif: horseman and barking dog at the verge, differently finished; both with ox-head corner motif; Rotterdam: left of the period from 1670 to 1700; 12,8 x 12,8 x 1,0 cm; right of the period from 1700 to 1730; 13,1 x 13,1 x 0,9 cm

For an approximate dating of Delft tiles the following distinquished marks - beneath the nail holes (see the link "Production Process") - should be checked:

colour of earthenware or back of a tile
thickness of a tile 
colour and overglaze 
design of motif and border

Colour of earthenwar or back of tiles

Tiles from the end of the 16th to the middle or even the end of the 17th century were usually made of reddish clay. The reddish colour came from the high iron content in the Dutch clay.

That's causes the Dutch term „Tegel“, which complies with the german word for (red) brick („Ziegel“). 

During the 17th century more and more chalky earth was brought into the clay material, to effect a better fixing of the tin-glaze on the tiles. Therefore the colour of the earthenware, even starting from the middle of the 17th century, but surely from the beginning of the 18th century, became lighter and lighter, that means the colour now looked cream and later greyish-white.

Tiles of the 19th century wereas had mainly light, yellowish and also grey-white colours of the burned clay.

Three typical backsides:   

Since 1900 the tile raw material was made as a rule on a tile press. So that's why they have sometimes grooves at the back. Should the tile back produced with such grooves, beside a comparison between the colours of the burned clay, tiles of the 20th century can easily distinguish from tiles produced before 1900. 

Two typical tile backs with grooves: 

Back to top

Thickness of tiles

Tiles between 1570 and the middle of the 17th century were in comparison with younger tiles generally really thick, caused by the method of production. Therefore they were also heavy and resistent. I.e. the thickness of tiles made in the late 16th century until 1600 gradually decreased from about 1,9 cm (in seldom cases they also had a thickness of 2,0 cm) to about 1,5 cm. 

Those ones of the early 17th century were still about 1,5 cm thick, but shortly after 1,4 and 1,3 cm untill to 1,2 cm in the years from 1630 to 1640.

Even from the mid-17th century tiles had been produced thinner and were now mainly about 1,2 cm to 1,0 cm thick until to a thickness of 0,9 to 0,7 cm, especially at the end of the 17th century.

According to quality and production facility Dutch tiles mainly maintained this thickness between 0,7 and 0,8 cm since the 18th century into the 20th century.    

Three typical side views:

Back to top

Colour and overglaze

Between 1570 and 1630 the used colours corresponded mostly like to the Italian and Spanish/Portugese model. Tiles were coloured in yellow, orange, blue, green, red, violet and white, so-called polychrome tiles.

In the same period tiles were also painted in the typical dark blue or more seldom brown.

During the further 17th century the painters detached more and more from the polychrome patterns and tried to create their own designs. Hereto belongs above all a light-blue (well-known as the "Delft blue"), by imitating the at this time popular light-blue of the Chinese Ming porcelain.  

From the mid-17th century the blue painting of tiles became more and more popular (so-called monochromy, according to the taste of the early baroque time).

At the end of the 17th century again the dark blue was more popular closely to the colour of the Chinese porcelain of the Kang-Hi time.  

The so-called manganese colour (a light purple) appeared strongly in the late 18th century (the time of rokoko). This colour accorded – in contrast to other kinds of blue – to the contemporary taste.

Some times both colours can be found on one tile, whereby the earliest exemplars, starting from the mid-17th century, are quite rare (look fig. above).

The predominantly monochrome coloured tiles of the 19th and 20th century are kept in blue, from light to dark, as well as manganese with a partly reddish or brownish dash (see for a rare example of a single colour tile, painted in green, 1890 - 1920, the link "Production process" and there the link "Colours").

Collateral to the changes of the colour the overglaze changed, too.

Tiles of the late 16th and early 17th century were covered with a white tin-glaze and to the mid 17th century after being painted additional covered with a thin layer of a transparent lead glaze (so-called „kwaart“). The kwaart, which melted into a clear transparent layer, made the colours look clear and brigth and the surface shining. You can see this effect, which intensifies the colours on tiles in good condition.

By imitating the imagin of Chinese porcelain the white tin-glaze got a light-blue touch in the first half of the 17th century.   

For comparison:

Changes in the mixture of clay and tin-glaze made – starting from mid-17th century – the process of covering the tiles with a transparent lead overglaze dispensable. That process did'nt change hardly until today.

Back to top

Design of motif and border

While tiles until the end of the first half of the 17th century had complex, over the total center painted central motifs, partly in connection with wide borders and large corner motifs, 

the central motifs became smaller and simpler during the second half of the 17th century. The reason was on one hand to keep up the increasing demand, and on the other hand to decrease the costs of production. Tiles were now mainly monochrome, the borders around the central motifs were gone, and the patterns of the corner motifs got smaller, too.

When at the beginning of the 18th century the technique of production enabled savings as well of clay, overglaze (because the second glazing-cycle was not needed any longer) as of colour pigments, again the central motif was mostly painted over the hole center of the tiles.  

A similar change took place by the patterns of painted borders around the central motif.

Between 1570 and the first half of the 17th century the Italian circle band and the Spanish (Moorish) diamond were predominant. Starting from 1620 already archway- and baluster-borders were used. Inside the borders the central motif were painted, namely portraits, soldiers, animals, flowers or fruits. 

This kind of pattern gained more and more importance beside the until 1635 predominating ornamental tiles. The latter ones connected geometric pattern of crosses or stars (renaissance motifs).

Starting from 1620 the Chinese accolade was also used as border in different typs. The same goes for the oval around the central motif, which was even seldom used.  

Approximately since 1630 the jagged rombig border (diamond) appeared more frequently. This type of border looks like a square put on one corner, surrounded by jags. The corners often are decorated with three dots (three in a triangle connected points, the symbol of trinity).

Flowers in jagged diamond: rigth with three dots at the corners, 13,2 x 13,2 x 1,4 cm, left orange tulip, Rotterdam, 13,1 x 13,1 x 1,2 cm. Both polychrome; corner motif modified French lily; 1630 - 1650

In addition to the mentioned borders the artists painted a lot of further fraiming patterns, e.g. as well the quatrefoil and the octofoil as the bracketed arch, which are found on tiles not so often, but even were well-used.

In the 18th century the circle (constructed from two or three rings) dominated above the octagon and the square, which all were the most common borders on Dutch tiles since the 19th century. 

Of course several tiles of the 17th and 18th century didn’t have any borders. Above all since the 2nd half of the 17th century a border around the central motif was missing. 

The only decoration which still remaind were the characteristic corner motifs (see link corner motifs). As well at this time tiles without any border and corner motifs were produced, namely to reduce the production expenses.  

With the second quarter of the 18th century so far a change can recognize too, as now tiles were produced also in that way, that the painting streches the whole surface of a tile, so called overall paintings. Since 1725 mainly detailed painted landscape tiles have been made in that manner. 

By the way, such "openluchtje"-tiles can already be found during the period from 1600 to 1625, in which proportionally often sea creatures and fish, but also soldiers have been pictured particularly impressive and colourful (polychome).

Back to top
 

Here a choise of typical borders