Indus Valley Oil Lamp, ca. 3rd - 2nd Millenium BC. A choice stone oil lamp from the Indus Valley, ca. 3rd - 2nd Millennium BC. This superbly detailed example is 5ï¾ long and is carved from blue-grey chlorite characteristic of this region. This diamond-shaped lamp is divided into four openings, with the surrounding areas decorated with nicely carved design elements, including a central floral design. Rare type, with strong mineral encrustation. Ex Khan estate. Value range: $300 - $500.