The activity of Hernandez was very great. From the date of this altar-screen we have a vast number of carvings executed, or supposed to have been executed by him. His studio became the centre of the artistic activities of his day, for the amount of his work necessitated the employment of assistants. This has led to confusion, and there are many carvings attributed to Hernandez which cannot be accepted as the work of his own hand. It is fortunate that the distinctive qualities of his work make it possible to recognise at once those carvings and statues that have been fathered on his name. Hernandez placed special importance on the colourisation of his statues. In an interesting contract made with his habitual polychromist, Diego Valentin Diaz, we find the most minute details laid down, enforcing the care with which the work is to be carried out. The colours chosen “are to be those which are permanent”; “the flesh must be _mate_,” as, it will be remembered, was enforced by Pacheco, and “in each case the colouring must be suitable to the model painted,” as, for example, “Jesus the tint of an infant, the Virgin that of a young woman, St. Joseph that of a man,” while “the hair and eyes must also be in harmony.” Also, “gilded stuffs and damasked are to be avoided,” and “gold is to be used sparingly on laces and fringes only.” The effect to be aimed at is harmony and truth to nature. It is by this restriction to a sombre and quiet scheme of colour, so different from the startling and tumultuous effects, glittering with gold, of Juni, for instance, that the polychromes of Hernandez may be recognised. His colours, always quiet, give an effect of having been worked on silver or ivory. The polychromes that do not manifest these tones are not by Hernandez; when they bear his name they must have been executed by his pupils apart from his direction. Examples of such spurious works are the immense and highly coloured Sta. Teresa in the Valladolid Museum, and also the _Pasos_, or groups from the Passion, highly praised by the Spanish writers and used in the religious processions of Valladolid, which have been attributed, certainly erroneously, to Hernandez. Authentic works of Hernandez may be seen, first in the churches, convents, and museum of Valladolid, and also at Madrid, Palencia, Vittoria, Salamanca, Zamora, Pontevedra, Medina del Campo, and other towns. But in no case must the attribution to Hernandez be accepted without an examination of the works themselves. Those which do not display his qualities, especially in their colourisation, must be accounted as the work of his pupils. Hernandez continued the practice of Juni in carving his statues as separate figures or in isolated groups. Almost without exception he used wood as his material.