The Santo Caliz

The Santo Caliz is a composite object about 17 centimetres tall. Its heart is a small, plain cup of dark reddish agate, polished to near-translucency, which archaeologists date to a Greco-Roman or eastern Mediterranean workshop of roughly the first century BC to the first century AD, a plausible date and place for a vessel used at a Jewish supper in Jerusalem. Below it, medieval goldsmiths added a stem and a foot made from a second, inverted agate cup, joined by a golden knop set with pearls and gemstones. Devotion holds that only the upper bowl could be the cup of the Last Supper; the mount is the work of later centuries that gave the relic a fitting form.

Among the many objects claimed as the Holy Grail, the Valencia cup is the one that scholars treat most seriously, because the bowl is genuinely ancient and its documented Spanish history is long, even if the chain back to the first century rests on tradition rather than record. The cathedral is careful to present it as a venerated relic with a strong claim rather than a proven one.