January Birthstone: Garnet

What is the January birthstone

The January birthstone on the modern US list is garnet, and it has held the month since jewelers standardized birthstones in 1912. Garnet is a group of minerals that share one crystal structure, with the general formula X₃Y₂(SiO₄)₃, where X and Y stand for metals such as calcium, magnesium, iron, manganese, aluminum and chromium. Much of the garnet mined today never becomes jewelry: it is crushed for sandpaper, sandblasting and waterjet cutting, as the USGS garnet fact sheet explains. See every month on the birthstone chart.

January birthstone color

The January birthstone color is deep red, the shade of almandine and pyrope garnet, but garnet also comes in orange, yellow, green, purple and pink. Spessartine runs orange, grossular ranges from green to cinnamon brown, and the rare green demantoid belongs to andradite. If red is not their color, a January birthday still has options, and GIA's January birthstone page shows the range.

Types of garnet

Types of garnet that turn up most often as raw crystals are almandine, pyrope, spessartine, grossular and andradite, with uvarovite as a green rarity:

Almandine: iron and aluminum; deep red to purplish red; the classic garnet in mica schist.
Pyrope: magnesium and aluminum; blood red; the Bohemian garnet of Victorian jewelry.
Spessartine: manganese and aluminum; orange to reddish orange.
Grossular: calcium and aluminum; includes green tsavorite and orange-brown hessonite.
Andradite: calcium and iron; includes green demantoid and black melanite.
Uvarovite: calcium and chromium; emerald green crystals, usually too small to cut.

Raw garnet as a January birthday gift

Raw garnet makes a good January birthday gift because it looks the way people expect a crystal to look, sharp-edged and dark red. Garnet grows in the cubic system, often as dodecahedrons (12 diamond-shaped faces) or trapezohedrons (24 faces), either loose or sitting in dark, glittering mica schist. A single dodecahedron fits in a palm, and a slab of schist dotted with red crystals reads like a small sculpture. Look for a label that names the garnet type and the locality. New pieces arrive in drops, and the list hears first.

January birthstone meaning

The January birthstone meaning, in crystal lore, is protection, loyalty and steady energy. That is belief, not chemistry. The history is solid, though. The name comes from the Latin granatum, for the pomegranate, whose seeds look like small red garnet crystals. Garnet has been used as a gemstone since the Bronze Age, Anglo-Saxon goldsmiths set cut garnets into the treasures of Sutton Hoo and the Staffordshire Hoard, and legend says travelers carried garnet for safe passage.

How to tell if garnet is real

How to tell if garnet is real is easier with raw crystals than with jewelry. A sharp dodecahedron is hard to fake and too cheap to bother faking. In jewelry, red glass is the usual stand-in, so look for round bubbles under a loupe. Old pieces may be garnet-topped doublets, a thin slice of garnet fused onto colored glass. Lab-made YAG and GGG share garnet's structure, but neither is a natural garnet. A strong magnet often tugs on almandine and spessartine, while red glass does not move.

Garnet care

Garnet care is simple: at 6.5 to 7.5 on the Mohs scale, garnet is tough enough for a desk or shelf, and it is water safe and sun safe. Rinse a raw piece in plain water and dry it on a towel. Garnet does not fade in daylight, so it can sit in a bright window without losing color. Go easy on garnet in schist, since the mica around the crystals is soft and flakes if scrubbed.