Most probably produced in 1375 (the date shown on the perpetual calendar accompanying the maps), it is attributed
-although without certainty - to Abraham Cresques. It presents remarkable similarities
with Dolcert's portolan chart insofar as the western area is concerned. However, its rendering of the oriental half
was not based merely on the experiences of Mediterranean sailors but also on a variety of sources including the
accounts of Marc Polo's journeys in the late XIIIth century.
It originally comprised 6 vellum leaves folded down
the middle- the leaves are now cut in half. It is painted in several colours and gold and silver. Each half-leaf
is mounted on one side of the five wooden panels, the first half of the first leaf and the second half of the
last leaf being mounted on the inner boards of a brown leather binding. Each leaf measures approximately 65x50 cm
giving an overall size of 65x300 cm. The first two leaves contain cosmological, astronomical and astrological
texts translated into Catalan with information on tides and methods of reckoning time at night. There are several
accompanying illustrations, a tide table, a perpetual calendar, the figure of a man marked with the signs of the
zodiac, and a large circular chart framed by the four seasons giving information on the zodiac, the seven known
planets and a diagram of the constellations.
The four remaining leaves make up the map itself, two of which
feature many illustrations of cities, the Christian ones being marked by a cross and others by a dome. The
last two leaves are a fairly standard form of the 1339 portolan chart of Angelino Dulcert but it is the first
ever portolan chart to show a drawing of the compass rose.