Luxembourg, Grand Duchy. Adolphe de Nassau CU 10 Centimes. 1889. ESSAI strike. GRAND-DUCHÉ DE LUXEMBOURG, crowned coat-of-arms, mintmarks below / RÉGENCE DE DUC ADOLPHE DE NASSAU, denomination within wreath; date below. KM E15. 

NGC graded MS 64 RB (5710118-012).

From the inventory of a UK dealer.