The Clapp oscillator was devised as an improvement over the Colpitts oscillator by virtue of adding one ... but they are convenient values for illustrating just how these little beasties work. We use ...

We’ve read a lot about oscillators, but crystal oscillators seem to be a bit of a mystery. Hobby-level books tend to say, build a circuit like this and then mess with it until it oscillates.

The post looks at a Colpitts oscillator. You can usually tell a Colpitts oscillator by remembering it starts with C and the feedback loop has a split capacitor (as opposed to a tapped inductor).