Earth Sciences & Geology

Does anyone know the name of these gemstones/crystals

Ive got some gemstones and they arent labeled. here is a picture of them : http://img198.imageshack.us/i/imgp4073j.jpg/-from left to right blue chalcedony (most likely) quartzamythest agaterock cryst

Will it speed up or slow down

Look, if we all drive east and hit the breaks the same time will it speed up or slow down the rotation of the earth?-Neither.We would all have to get our vehicles going towards the east first.Then sto

Please help with this question on soil? (^_-)

Hello there! Well, my question is: How are the soils that develop under grasslands might be different from those that develop under forest vegetationn? What causes them to develope differently? Thank

How long before the Straight of Gibraltar is closed

How many years until the African plate meets the European one at the Straight of Gibraltar, sealing it off from the Atlantic?-At the current speed that the African Plate is slipping under the Eurasian