Pyrite skulls from Peru. Very rare.

Pyrite or iron pyrites is a mineral with the formula FeS2 (chemical name: iron disulfide). It is an important mineral iron ore and sulfur. It is often well-formed (euhedrische) of crystals in the form of a cube with characteristic striations and with a gold sheen. It is also called mad tinsel or gold (gold of the English fool's) because it sometimes for gold as was. However, the name cat gold is sometimes used incorrectly, this refers to yellow mica or resin. Because pyrite occurs largely can create the illusion of great wealth. However, pyrite is not worth very much (although it can be sold). It is found, together with other sulfur-containing minerals, but also with oxides, in quartz veins in sedimentary rocks in the carbon beds and as a replacement mineral in fossils. Pyrite is a disulfide with sulfur pairs (S2) 2, and Fe2 + ions in an octahedral surrounding t2g6 went into a low spin state. As a result of the fact that both ions have a closed configuration, it is a diamagnetic semiconductor. When the weathering of pyrite occur iron (hydr) oxides, which also releases sulfuric acid. This acid may then enter into reaction with other minerals, and thereby lead to the formation of, for example, gypsum, and aluniet jarosite. An important source of pyrite is the island of Elba. The name pyrite is very old, derived from the ancient Indo-European word pyr (fire, cf. Eg pyrotechnics fireworks art, or the English pyre (pyre) because one could create sparks by pyrite against flint or iron to catch on. Today The day we hear something different under flint (a form of SiO2). Other names that one of pyrite against can get his ferrosulfide, sulfur, iron and less common words ijzerblende and iron pyrites. Pyrite was used to be sold adulterated gold since the gold-like shine . However, the gloss changes when the glossiness flat tilts, with gold the gold shimmer is the same. Also, pyrite angular, with sharp edges and hard, while gold is round and soft.
 
The crystal skulls are from quartz or rock crystal faceted artwork in the shape of human skulls. This appeared in the second half of the nineteenth century and were originally assigned to various precolumbiaansebeschavingen. Research in the last decade of the twentieth century, among other things with the aid of a scanning tunneling microscope showed that in each case a number of these skulls are counterfeits. These are made with grinding tools which until the second half of the nineteenth century developed werden.Er is a strong presumption that produced some of the crystal skulls were commissioned by the French dealer Eugène Boban and sold by him. One of the most famous skulls is the Mitchell-Hedges skull. This would have been found by the British adventurer FA Mitchell-Hedges in a space under the ruins of Lubaantun in Belize. Later he appeared to have this skull bought privately in the London auction house Sotheby's. His wife gave as his reason that he gave the skull just as collateral to someone and it had repurchased through Sotheby's. After the death of Anna Mitchell-Hedges, the skull came into the possession of Bill Homann. In the nineties it became clear that the Mitchell-Hedges skull was a fake. In the meantime, the necessary hypes and legends formed around the crystal skulls. Their so-called site they'd centuries ago by the Mayans, the Aztecs or even 0udere precolumbiaansse civilization were manufactured. Would have these psychic abilities and would never right may look in the eyes. According to another legend, they would have an extraterrestrial origin. There would find thirteen of on earth. Once reunited, they would share their knowledge with humanity. Even now play the skulls still has a role in some of the New Age community.

In fiction:
• In the movie Indiana Jones and the Kingdom of the Crystal Skull from 2008 all the above legends are combined.
• The hidden crystal, a book by Manda Scott, is about the crystal skulls and the 2012 phenomenon of the Maya.
• In the 21st episode of season 3 of the science fiction series Stargate SG-1 2000 (Crystal Skull) Daniel Jackson disappears when he looks into a crystal skull.

• The Assassin's Creed series refers to the skulls, where the ancient artifacts with mysterious powers.

Gemstone skulls. Gemstone skulls are already popular and mysterious to many cultures since many decades. The skulls have a very different meaning. Celtic skulls symbolize Time, Strength, creation, initiation and concentration. Celtic culture believes the skull is a seat of power and strength. Some texts refer to the cranium as the seat of the soul. Archaeological findings tell us that the ancient Celts skulls sacrificed to holy wells. The skull is universally recognized as the symbol of life and death. More recently, the skull linked to death and embracing our mortality. In ancient times, the skull was sometimes for life. Skulls and skeletons are the symbol for the Mexican holiday, the day of death. The skull and crossbones is a popular symbol for pirates and poison. Some healers use skulls to see visions of the past, present and future. including rose quartz, rock crystal, rhodonite, aventurine and hematite.