What Delft Blue actually is

Delft Blue is one of those names that everyone recognises and almost nobody can define. It is not a material, not a technique and not a brand. It is a look: dark cobalt blue painted or printed on a white ground, on ceramic, in a particular Dutch idiom. Understanding where that look came from makes it a great deal easier to judge what you are actually buying.

It started as an imitation

In the early seventeenth century the Dutch East India Company was shipping Chinese porcelain into the Netherlands by the crate. Nothing made in Europe came close. It was thin, hard, brilliantly white and decorated in a blue that seemed to sit inside the glaze rather than on top of it. It was also expensive enough that owning a single piece said something about you.

When the supply from China was disrupted around the middle of the century, Dutch potters saw an opening. They could not make porcelain, because nobody in Europe yet knew how. What they could do was make earthenware, coat it in a white tin glaze so it looked like porcelain, and paint it in blue. That workaround is Delftware.

Why cobalt, and why blue on white

The colour was not an aesthetic preference so much as a chemical constraint. Very few pigments survive a kiln. Most burn away or turn muddy at the temperatures needed to fuse a glaze. Cobalt oxide is one of the exceptions: it goes into the kiln as a dull grey smear and comes out as a deep, stable blue. If you wanted decoration that would still be there in two hundred years, blue was close to the only option.

The white came from tin. A tin-based glaze turns opaque and creamy white when fired, which hid the yellowish clay body underneath and gave the painter a clean surface. Blue on white was, in other words, what the technology allowed. It became a style afterwards.

How a city ended up owning the name

Delft was not the only Dutch town making tin-glazed earthenware. It simply made the most of it, and made it best, for long enough that the name stuck. The city had breweries going out of business and their large buildings, water supply and kilns were easy to convert into potteries. At its peak Delft had dozens of workshops, each with its own mark.

Almost all of them closed. One of the original Delft potteries, De Porceleyne Fles, survived and still operates today as Royal Delft. It is a separate, real company with its own history. Worth knowing, because the phrase “Delft Blue” is used by everyone and the name Royal Delft belongs to one of them.

Earthenware, not porcelain

This matters if you ever handle an antique piece. Delftware is earthenware: a soft, porous, buff-coloured clay body under a thick opaque glaze. Porcelain is dense, vitrified and translucent at the edges. Hold a genuine old Delft plate up to the light and no light comes through. Chip the rim and you see pale clay, not white glass.

It also means old Delftware chips easily, which is why so many surviving pieces have nibbled edges. Collectors treat a little damage as normal rather than disqualifying.

Antique, modern, and the word “style”

Almost everything sold today as Delft Blue falls into one of a few groups, and the price gap between them is enormous.

• Antique Delftware: made in the seventeenth or eighteenth century, hand-painted, tin-glazed, usually marked. Auction territory.
• Twentieth-century factory ware: hand-painted or transfer-decorated by established potteries. The souvenir windmills and shoes mostly live here.
• Contemporary hand-painted work: made now, by hand, by working ceramicists. Genuinely expensive, and it should be.
• Delft-blue style: new pieces designed in the idiom and produced with modern methods. Honest when it says so, misleading when it does not.

What you are looking at today

None of those categories is dishonest by itself. The problem is only ever the description. A modern printed tile sold as a modern printed tile is a good object. The same tile sold with a vague hint of antiquity is not. If you want to be able to tell the difference in a shop or a listing, we wrote a separate piece on exactly that: how to recognise what you are buying.

And if you want the other half of the story, the wall tile followed its own path away from the decorative plate. That path is covered in the history of the Dutch tile.