Valpolicella Ripasso is a form of Valpolicella Superiore made with partially dried grape skins that have been left over from fermentation of Amarone or recioto. Winemaking in the region has existed since at least the time of the ancient Greeks.
Barium chloride, or any other barium salt, should burn with a green flame. When a barium salt is burned, the thermal energy is transferred to the outer electrons of the barium ions. They gain enough energy to excite them to a higher energy level. They then drop back to their ground state, releasing energy.
Firescale (a.k.a.: firestain, stain) is that grey/black/purple stain that appears on the. surface of sterling silver after it has been heated. When sterling silver is heated in. the air, the oxygen in the flame and in the atmosphere attacks some of the copper. alloy near the surface. This forms a copper oxide on the surface of the metal.