Delftware solved a commercial problem with a chemical trick: tin oxide turned a glaze opaque milk-white, so cheap red Dutch clay could pass for Chinese porcelain. Everything else follows from that surface. The white glaze is the ground; the cobalt is brushwork laid onto it, never a field printed behind it.

At 1650 the blue is still light — a lavender wash carrying dark blue-black outlines — before the full-strength cobalt of the late-century workshops. Delft painters copied Kraak plates and quietly made them Dutch: chinoiserie sprigs sharing a rim with tulips, windmills and low-horizon landscapes.