Know all about Gossan and Rhomb Porphyry properties here. All properties of rocks are important as they define the type of rock and its application. Gossan belongs to Metamorphic Rocks while Rhomb Porphyry belongs to Igneous Rocks.Texture of Gossan is Rough, Sandy whereas that of Rhomb Porphyry is Aphanitic to Porphyritic. Gossan appears Dull and Banded and Rhomb Porphyry appears Rough. The luster of Gossan is metallic while that of Rhomb Porphyry is subvitreous to dull. Gossan is available in brown, brown- black, gold, green, rust colors whereas Rhomb Porphyry is available in black, brown, colourless, green, grey, pink, white colors. The commercial uses of Gossan are cemetery markers, commemorative tablets, gemstone and that of Rhomb Porphyry are an oil and gas reservoir, as a feed additive for livestock, metallurgical flux, soil conditioner, source of magnesia (mgo).