Margarita Mine, Amatitlán, Eduardo Neri Municipality, Guerrero, Mexicoi

Regional Level Types
Margarita Mine	Mine (Inactive)
Amatitlán	Diggings
Eduardo Neri Municipality	Municipality
Guerrero	State
Mexico	Country

Amatitlan amethyst is easily recognized, and distinguished from Veracruz amethyst, by the crystal shape and coloration. At Guerrero the elongated amethyst crystals tend to be a bit fat around the lower and middle area, and taper to typical quartz terminations (Las Vigas crystals are rarely tapered).

The amethystine color-a deep reddish purple comparable to the best Siberian amethyst-is generally very dark and rich in the core of the central and lower area but fades to colorless/white at the outermost zones and the termination (most Las Vigas crystals become darker toward the termination,and are nowhere as dark as the Guerrero crystals). Sharply contrasting phantoms are common. Rarer crystals are concentrically zoned, with nondescript milky outer zones concealing rich purple interiors. Color patterns vary greatly between occurrences and even within individual pockets; many finds are sufficiently characteristic in habit or coloration to be immediately distinguished from specimens from other pockets.

Crystal sizes in the 5 to 10-cm range are not uncommon, and rare individuals over 60 cm and 45 kg have been found (Wayne Thompson, personal communication). Clusters tend to be somewhat divergent and highly attractive. The crystals are often found coated by manganese oxide.

There are a number of "mines" in the area...most shallow adits or cuts into the many veins that lace the area. Miners tend to work one for a while and move on to the next, so unless you have very specific information about which mine your piece comes from it is probably safest to label the simply "Amatitlan" for the nearby village

As Manuel Ontiveros pointed out his 2004 article in Mineralogical Record (with Wendell Wilson and Peter Megaw), the Margarita mine was named for his older sister, Margarita...beloved, but no saint apparently. Where the Santa came from no-one seems to know although Panczner (1987) cites it.

Other Regions, Features and Areas containing this locality

References