MSN home
Mail
My MSN
Sign in
encarta
greeting cards
more
Hotmail
Messenger
My MSN
MSN Directory
Air Tickets/Travel
Autos
Careers & Jobs
City Guides
Dating & Personals
Election 2008
Food & Entertaining
Games
Green Living
Health & Fitness
Horoscopes
Lifestyle
Maps & Directions
Money
Movies
Music
News
Real Estate/Rentals
Shopping
Sports
Tech & Gadgets
TV
Weather
White Pages
Yellow Pages
encarta
®
Home
Encyclopedia
Dictionary
Atlas
K-12 Success
College & Grad School
Degrees & Training
Quizzes
More
Additional Reference Materials
Thesaurus
Translations
Multimedia
Other Resources
Education Resources
Foreign Language Help
Project Planner
Scholarships & Financial Aid
Jobs & Internships
Coffee Break
Ask Bill Nye the Science Guy
Top 10 Lists
Columns
On This Day
Encarta Products
Help
Related Items
from
Encarta
Shale
geodes
geography of United States Heartland
Grand Canyon
mechanical sedimentary rock
oil shale
oil shale as a fuel source
Geode
Geode
, in geology, a more or less spherical structure, several centimeters wide, found in limestones and shales. A geode first formed as a cavity with...
View article
MSN Privacy
Legal
Advertise
Newsletter
Worldwide
Feedback
Help
© 2008 Microsoft
Hotmail
Messenger
My MSN
MSN Directory
View article
