What is meant by Hydro-Thermal Veins?
A. Many good specimens are obtained from mineral veins. High temperature fluids deposit minerals in cracks and fissures in rocks these are often called hydrothermal veins and are frequently worked as sources of ore, they often contain colourful specimens and good crystals. Sometimes weathered- out cavity linings called Geodes are lined with well-shaped crystals and many fine specimens of Amethyst occur in these. Many crystal formations occur in Hydro- thermal veins. The largest are not always the most spectacular and some of the smallest crystals are the most perfectly formed ones.
