An antique double miniature portrait paintings on enamel plaque by French artist Mathieu Deroche. Circa late 19th century. The portraits show a man and a woman in oval, most likely a married couple, dressed in Victorian fashion. Framed. There is a stand on the reverse side. Mathieu Deroche, 1837 to 1904, is a French 19th Century famous photographer and painter. He is best known for his portraits, some of which are colored and transferred to ceramic and vitrified by a process that bears his name: Deroche Process or Mathieu Deroche Process. European Decorative Antiques And Collectibles, Home Decor.