Ruby / Corundum:
Conch is a common name that is applied to a number of different medium to large-sized sea snails or their shells. The term generally applies to large snails whose shell has a high spire and a noticeable siphonal canal (in other words, the shell comes to a noticeable point at both ends). Conch jewelry is set with queen conch shells that are precisely cut and polished to the desired design.
Ruby / Corundum is a crystalline form of aluminum oxide (Al2O3) typically containing traces of iron, titanium, vanadium and chromium. It is one of the naturally transparent materials, but can have different colors when impurities are present. Transparent specimens are used as gems, ruby if red and padparadscha if pink-orange. All other colors are called sapphire, e.g., "green sapphire" for a green specimen. Because of corundum's hardness (pure corundum is defined to have 9.0 Mohs), it can scratch almost every other mineral.