Hematite ps. after Magnetite var. Martite

This is quite an amazing miniature specimen composed of aligned rows and columns of superbly crystallised Hematite pseudomorphing after Magnetite, a pseudomorph given the specific name Martite.  The alignment of the octahedral crystals is so regular it would appear to be man-made in the laboratory but has its origin in the volcanic fumaroles of the Payún Matrú volcano in mid Argentina.  Payún Matrú is a shield volcano within the Andean Volcanic Belt and is particularly famous amongst mineral collectors for these fine pseudomorphs.  The specimen is composed entirely of precisely orientated Hematite crystals of metallic, steely greenish-blue dark grey with a stunning bright specular lustre.  This really is a fabulous little specimen.