Chalcedony is the name for a group of stones made of cryptocrystalline or microcrystalline variety of quartz, this means that without high magnification, the quartz crystals are too small to be seen. Stones which included in this group are jasper, agate, petrified wood, fire agate, bloodstone, tiger eye, chrysoprase, carnelian, onyx and sardonyx. The name of the gem is derived from the name of the ancient Greek town called as Chalkedon in Asia Minor.
Difference Between Condominiums and Apartments
Have you ever wondered why some people call their place of residence a condominium and others an apartment? Though these two terms are usually used interchangeably, but they are not exactly the same thing. Condos (or also called as condominiums) and apartments are very similar. There is no way we can know whether it is an apartment or a condominium by just looking at the building, or even visiting it. But in fact, there are differences and that also significant ones.Difference Between Townhouse and Duplex
Duplexes and townhouses are different in their construction. A duplex is a two storey building but each storey has its own entrance so that two families can live in that building. A town home or also called as townhouse, is a row of houses attached to other houses.Difference Between Concrete and Asphalt - Which is Stronger
Both asphalt and concrete are popular and strong materials to pave driveways and roads with. These two durable materials perform well in the rain and cold and can last for many years if they are maintained well. However, each has its advantages and disadvantages: