Some measure of compensation for the unfortunate lack of actual examples of Italian Quattrocento jewellery is obtained, apart from their representation in pictures, by the very remarkable use that was made of jewel forms for the marginal decoration of manuscripts. Such enrichments of the borders of missals, etc., by means of painted jewel ornaments, would seem to be but the direct outcome of the system whereby most of the painters, sculptors, architects, and no less eminent miniaturists received their first instruction in art in the workshops of the goldsmiths. It is certain from their quality that the jewels represented in manuscripts, generally in their natural size, are the work of artists well acquainted with the jeweller's art, whose eyes were further impressed by the embroidered edgings of ecclesiastical vestments enriched with jewel ornaments and sewn with pearls and precious stones. In painting with corresponding luxury the border decorations of church missals, the miniaturists have obviously not drawn on their imagination, or constructed jewel forms in a mere haphazard manner. The individual pieces, often complete jewels, are just such as might at the time have been found on the shelves of some goldsmith's workshop. Among the most skilful of such reproductions of jewels are those in the celebrated choir books of the cathedral of Siena, particularly the pages painted by Liberale di Giacomo da Verona, who worked at Siena from the year 1466. An examination of these illuminations reveals Liberale as an artist thoroughly conversant with the jeweller's craft: so that his work, together with that of his followers, such as the Florentine Giovanni di Giuliano Boccardi, the Dominican Fra Eustachio, Litti di Filippo Corbizi, Monte di Giovanni, Antonio di Girolamo, the famous Attavante, and the various miniaturists of King Mathias Corvinus of Hungary, apart from its charming execution, constitutes a veritable storehouse of information respecting the ornaments of the period. Particularly fine examples of jewelled and enamelled decorations are also contained in choir books in the cathedral of Florence, missals in the Barberini Palace, Rome, a Bible of Mathias Corvinus in the Vatican Library, several books in the Brera at Milan, and the fine Glockendon missal (_circa_ 1540) in the Town Library at Nuremberg. More important perhaps than all is the Grimani Breviary, now in the Library of St. Mark's, Venice. The ornamentation of this famous work, the product of a Flemish artist of the final years of the fifteenth century, displays a northern naturalism favourable to the striking representation of jewel forms, and serves to illustrate the close and active relationship then existing between the Flemish and Italian goldsmiths.[121] [121] The whole of this magnificent work has been reproduced by Sijthoff, of Leyden, under the direction of Scato de Vries and Dr. S. Morpurgo.