Since the the introduction of the arabic word /"anbar/ in the 11th century in European Languages, (fr. ambre; eng. amber from lat. ambra), this word has been used to define two quite different substances: some sort of stone and a perfume. Contemporary lexicographers believe that ancient authors have recognized these two substances as the same and this identification has led to a semantic confusion. These lexicographers, however, have not throughly explained how this terminological confusion has taken place. The source of this confusion has been seemingly justifiable since the mode of extraction of these two natural substances from the sea is the same and so it would be evident that this confusion must have occured. This supposition is not based on medieval documents. The study of the historical documents shows that the designation of these two substances by the same word is problematic. Europeans who have extracted the amber from the Baltic Sea and well knew this substance have naturally assigned local terms to what is known later as amber. On the other hand, the main part of medieval knowlege on amber in the West comes from the oriental sources in Arabic language which the European scholars have exploited and translated in Latin (known as lapidaires in french). In the meanwhile, these main oriental sources have always distinguished the amber ("fossil resin", named kahroba) from the amber as a perfume (named "anbar). So this unexplained confusion apprears somewhere in the West during this period despite the clarity of the classical latin sources (Tacitus, Cassiodorus) as well as the Arabic literature on the subject.