Complex sentence: The oldest remains in the Aljafería Palace, together with other interesting elements like capitals, reliefs and inscriptions, were made using alabaster, but it was during the artistic and economic blossoming of the Renaissance that Aragonese alabaster reached its Golden Age.
Split into simpler sentences: The oldest remains in the Aljafería Palace, together with other interesting elements like capitals, reliefs and inscriptions, were made using alabaster. But it was during the artistic and economic blossoming of the Renaissance that Aragonese alabaster reached its Golden Age.