Yeah, Simmons.. Books are your freidns.. However, using them to compare rocks to rocks etc.. is a good thing and often I used books like "Crystal Bible" by Judy Hall.. whcih has a diffeant point of view on what a rocks properties might be.. This is where the lines get crossed.. Although the books are great to help you id stuff you find.. most of the books have their own view of what the minerals properties are.. and they doint see eye to eye.. So use them to find out what soemthing is.. as for what something can provide you with (power or propeties) wise.. best trust your own judgement.