There are basicly 3 types of crystals:
A) Standart crystals, these are the crystalst that everybody uses for uC...
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B) Low profile crystal, its the same as the above just smaller:
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C) Cylindrical crystal, also the same but size is very small and can be manufactured for low frequency, uses in the watches industry a lot.
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E) This one is not a crystal but a full oscillator inside a metal case , its supply a very stable square wave, very good component if to use instead of an RC oscillator.
If you are using this one for you uC you should look in its specifications for connecting an oscillator instead of a crystal...
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You can use either of the above but the cheapest solution is the standart crystal.