The Stone Sailors Refused to Sail Without

Picture a Roman merchant ship in a storm, somewhere between Alexandria and Ostia. The grain in the hold is worth a fortune and the sea does not care. Somewhere on that ship there is a sailor with a small blue-green stone, and if the accounts that survive are right, he might do something that seems strange to us: he might throw it into the waves.

Not because it failed him. Because it was the most valuable offering he had, and the sea, in his understanding, belonged to a god who could be reasoned with.

The stone named after the sea itself

Aquamarine takes its name from the Latin aqua marina, seawater, and the Romans were not being poetic when they named it. To them, the resemblance between the stone and the sea was not a coincidence. It was evidence. A stone the exact color of calm water had to have something to do with the power that governed water.

That power had a name: Neptune, or Poseidon in the Greek telling. Aquamarine was held sacred to him, and over the centuries the stone became known simply as the sailor's stone. Greek and Roman sailors carried aquamarine amulets on voyages, and surviving accounts describe amulets engraved with the image of Neptune, sometimes shown riding his chariot across the waves. The logic was direct: a stone sacred to the lord of the ocean would carry his favor and restrain his anger.

What the ancient writers actually said

The written record here is unusually good. Pliny the Elder, in his Natural History of 77 AD, described the sea-green beryls as especially esteemed, and a line long attributed to him captures how the Romans saw the stone: a gem that seemed to have come from a mermaid's treasure house in the depths of a summer sea. In the second century, a writer known as Damigeron recorded the stone's reputed virtues in a work on the powers of stones, including medicinal uses that sound strange today, such as preparations for ailments of the eyes.

A note of honesty, because you deserve it: ancient writers did not distinguish stones the way modern gemology does. Aquamarine is a blue beryl, cousin to the emerald, and the classical sources sometimes blur the beryls together. What is certain is that the sea-colored beryls attracted the maritime beliefs, and that those beliefs were strong enough to survive the fall of the empire that recorded them.

An heirloom belief

The sailor's stone did not retire when the legions did. The association between aquamarine and water carried into the seafaring cultures of northern Europe, where the stone kept its protective reputation even after Neptune's name was forgotten. In the medieval courts, aquamarine picked up a second life as a supposed antidote to poison, which made it popular in places where dinner invitations carried risk. It was set into royal regalia: the Crown of Saint Wenceslas, made for Charles IV of Bohemia in 1346, carries aquamarine, and in 1608 Matthias II had aquamarines added to the Holy Crown of Hungary for his coronation.

From a sailor's pocket to a king's crown is a long climb for a stone. What carried it there was the same quality that made the sailors trust it: the sense that this stone held the calm of the sea inside it, and might lend that calm to its keeper.

The stone in your collection

Mineralogically, aquamarine is beryl, colored by traces of iron, and it is a genuinely hard stone at 7.5 to 8 on the Mohs scale, hard enough to survive daily wear for generations, which is why antique aquamarine jewelry still circulates. If you inherited a piece, or you were drawn to one at a gem show without knowing any of this history, the tradition says you responded to exactly what the Romans responded to. The color of deep calm, carried where you can reach it.

Many collectors today keep aquamarine for travel, especially travel over water, which is the old use wearing modern clothes. Others keep it for the calm alone, near a reading chair or a desk. There is no wrong placement for a stone whose entire history is about carrying stillness into unstill places.

One buying caution: genuine aquamarine's soft blue is often imitated with treated blue topaz or glass at tourist shops and gem shows. If the price of a large, vividly blue "aquamarine" looks too good, it usually is. The checks in our fake-spotting guide apply here, and the free 26-stone guide covers aquamarine in detail.

The traditions described here are part of cultural and spiritual history. Crystals are not a treatment for any medical or psychological condition. Please read our full disclaimer.