Carnelian

Chalcedony

6.5–7Hardness (Mohs)

SiO₂:FeChemistry

2Known origins & mines

Orange-red chalcedony of pharaohs and prophet rings alike — Egypt's tomb seals, Roman intaglios and Muhammad's silver signet. India's Khambhat (Cambay) has processed heat-treated carnelian for 4000 years; Brazil ships dyed material today.

Known origins & mines

Khambhat Onyx Workshops · India

Active mining · Legendary locality

Cambay has processed carnelian and onyx for 4000 years — Indus Valley beads traveled Mesopotamian trade routes; heat treatment mastery persi…

Nile Valley Carnelian Sources · Egypt

Historic mine · Notable deposit

Pharaonic Egypt sourced orange-red carnelian from Nubian desert wadis — tomb seals and heart scarabs traveled to Tutankhamun's burial from t…

Mineral family: Chalcedony

Chrysoprase Agate Black Onyx Jasper Blue Chalcedony Bloodstone (Heliotrope)