Male and female. The male isn't very masculine, but male nonetheless!
Taken from Wikipedia:
These stones have been termed "living stones" due to their own energy field and ability to "die." In a solid form, these stones have a hardness of 7.0. BojiŽ stones come in two types, male and female. The male stones are more textured and have large crystalline formations protruding from them, whereas the females are more smooth and rounded. There are more females than males.
Known to alternative healing practices to be a beneficial stone for treating arthritis and other disorders, these stones react to bioelectrical fields as well. The human body naturally produces a voltage that can be read by a multimeter. It is natural to have a charge between 5 and 30 millivolts (a pacemaker regulates the human heart with a 1 millivolt charge). If the reading is done from the palms of the hands without the stones, the body's natural charge is displayed fairly accurately. However, if a stone is placed in each hand and the reading is taken again through the stones, the reading will usually rise to above 100 millivolts and a polarity shift will be noted.
Blue BojiŽ Stones are extremely useful in extra body exploration, as they facilitate traveling and protect the body until the soul returns.
Now for those of you who aren't into new-age stuff, this is also said:
BojiŽ stones , are concretions composed of either iron sulfide, i.e pyrite and marcasite, or in some cases jarosite, which are found in outcrops of the Smoky Hill Chalk Member of the Niobrara Formation within Grove County, Kansas. They are typically associated with thin layers of altered volcanic ash, called bentonite, which occur within the chalk comprising the Smoky Hill Chalk Member. A few of these concretions enclose, at least in part, large flattened valves of inoceramid bivalves. The "female" BojiŽ stones are smooth concretions, which range in size from a few millimeters to as much as 12 mm (6 inches) in length. Most of these concretions are oblate spheroids in shape. The "male" BojiŽ stones are small polycuboidal pyrite concretions, which are as much as 7 cm (0.23 foot ) in diameter (Hattin 1982). These concretions will explode if thrown in a fire. Also, when they are either cut or hammered, they produce sparks and a burning sulfur smell. Because of this behavior, BojiŽ stones are sometimes mistakenly called and or misrepresented as "Kansas pop rocks" by some gem and mineral collectors. Some claim "Kansas Pop Rocks" are virtually identical to BojiŽ stones in composition, size, and shape. Other similar stones can be found in outcrops of sedimentary rocks all over the world. For example, pyrite and marcasite concretions can be found in the Mooreville Chalk Formation of Alabama and the Cretaceous chalks of Sussex and Kent, England.
However to date, there has been no conclusive evidence provided that proves or disproves other forms of pyrite concretions such as "Kansas Pop Rocks" have the exact same mineral make-up or offer the seemingly magnetic properties as true BojiŽ Stones offer. Many will argue, only true BojiŽ Stones hold the unique and phenomenal properties to seemingly include magnetic properties. In actuality, BojiŽ Stones are a 100% non-magnetic metallic mineral. This can be proven by the use of a quality, sensitive navigation compass. When True BojiŽ Stones are placed near a compass they will have no magnetic effect on a compass. However, both pyrite and marcasite concretions also lack any magnetic effect on compasses. Unlike pyrrhotite, pyrite and marcasite are nonmagnetic and only become magnetic if it is heated.
The pyrite or marcasite, which typically comprise "Kansas Pop Rocks", with time can decompose, sometimes quite quickly, into a white, powdery pile of secondary sulphate minerals. This process is commonly called "pyrite decay". However, there is conclusive evidence provided that true BojiŽ Stones will not and do not decompose like Kansas Pop Rocks are know to do. Coarse grained aggregates of pyrite crystals, "male" Kansas Pop Rocks are the most stable form of iron sulfide, while the fine-grained aggregates of marcasite, which comprise the typical "female" Pop Rocks, are most prone to decomposition. However, additional factors, including humidity; the presence or absence of microorganisms, i.e. the bacteria Thiobacillus ferrooxidans; and other factors will determine whether and how fast specific individual Kansas Pop Rock stones disintegrate. The sulphuric acid liberated by the decomposition of iron sulfide composing "Kansas Pop Rocks" often destroys both the labels and boxes in which such "Kansas Pop Rocks" might be kept. True BojiŽ Stones do not have these same negative effects as the "Kansas Pop Rocks" are know to have..
Male is on the right. They have a sheen to them. Start the bidding at 2 bucks. Winner can pm me and pay 4.60 for shipping. I got these a gem show last year.