The Netherlands (Holland) 10 Guilder gold coin, also known as the Dutch 10 Gulden or Gouden Tientje, is a historic gold coin that was issued in various years and has become a popular collector's item. These coins were made of .900 fine gold, meaning they contain 90% gold and 10% copper, and they generally weigh about 6.72 grams, with a gold weight of approximately 0.1947 troy ounces. The obverse of the coin typically features a portrait of the reigning monarch of the Netherlands at the time of minting, while the reverse usually depicts the Royal Dutch Coat of Arms along with the denomination and date. The design and the monarch portrayed have changed over the years, with notable examples including coins bearing the likeness of King Willem III, Queen Wilhelmina, and later Queen Juliana.