The mortars of the chateau Châtel-sur-Moselle (Vosges) were dated by ¹⁴C. Construction took place from the mid-11th century through the 12th century, with an addition in the 13th century and another in 1450. Of ten dates, two confirmed the time of the original construction and two the 15th century addition. The other samples were contaminated (diverse sources) and gave incorrect dates for the construction. A serious measurement cannot be done except by studying a number of samples.