Amazing item for collectors, very Beautiful antique and rare Portuguese astrolabe made of brass. The astrolabe is an ancient naval instrument, used to measure the height of the stars above the horizon. It is conventional to say that the emergence of the astrolabe is the practical result of several mathematical theories developed by famous ancient scholars: Euclid, Ptolemy, Hiparchof Nicaea and Hythetia of Alexandria. The astrolabe has 9 cm (3.54 inches) diameter, 1 cm thickness (4 cm at the largest parte) and weighs 431 grams (15.203 oz). International buyers are welcome. This item is in the category “Collectibles\Decorative Collectibles\Other Decorative Collectibles”. The seller is “pint_abil” and is located in this country: PT. This item can be shipped worldwide.