August

August's traditional birthstone is sardonyx, but the modern stone — added to the 1912 Jewelers of America list as an alternative — is peridot, so the two lists actually differ here. Sardonyx is a banded onyx and sard historically worn by Roman soldiers for courage, and often carved into seal rings and cameos. Peridot is olivine, nicknamed the "evening emerald" because it keeps its green colour even under lamplight; it's been mined since antiquity on Egypt's Zabargad island, and it's one of the very few gems ever found in meteorites.

The birth flowers for August are the gladiolus, symbolizing strength of character, and the poppy, tied to imagination and remembrance. Together they cover both sides of the month — the gladiolus standing tall, the poppy holding onto memory.