The Imperial Orb follows the formal concept introduced in the
Crown of Rudolph II (Kaiserliche Schatzkammer Wien). As in the Crown, the decoration consists of diamonds, rubies and pearls as well as a single large sapphire at the top of the cross. The wide, pearl-lined equatorial band of the Orb and the crown circlet are set with large diamonds, interspersed with pairs
of pearls embedded in enamelled rosettes. The space between is filled with
arabesques of enamelled gold. The enamelled bands with depictions of
fruit and animals, which quarter the imperial orb vertically, are based on
the bands enclosing the mitre of the Rudolphine crown, but are executed
with less subtlety. The front of the cross is decorated with diamonds
and rubies, while the back is covered with a rich trellis-work of enamelled
gold. The crowning sapphire is drilled and without facets. It is an old
jewel, perhaps from classical antiquity, and was reused here, thus
suggesting the continuity of power throughout the ages. The globe
of the Imperial Orb represents the world and is a symbol of the emperor’s
universal claim to power. Many details of the gold-work are in keeping with the style of the Sceptre (Kaiserliche Schatzkammer Wien), which bears the signature of Andreas Osenbruck. These parallels suggest the attribution of the Imperial Orb to the same goldsmith and permit the conclusion that Emperor Matthias had it made after 1612 in order to possess a uniform set of private insignia, along with the Rudolphine Crown and Sceptre. Osenbruck, the data of whose life are unknown, had previously worked for Emperor Rudolph II and was employed in November 1612 as court goldsmith to Rudolph’s brother and successor, Emperor Matthias (1557–1619).