Op-Amp Colpitts Oscillator

Colpitts oscillator can be implemented using op-amp as long as we have an op-amp with proper bandwidth. Here is an example of such circuit:

LT1190 or  LT1191 op-amps is used to serve as an excellent gain stages. Limiting the gain is done by two Schottky diodes, that maintain the signal at approximately +11dBm.  This circuit give a low distortion performance, the  second harmonic is approximately 37dB down, limited primarily by the clipping action of the Schottky diodes.  [Circuit schematic diagram source: Linear Technology Application Notes]