JJ wrote:
There is a drop in freq for Pierce and Colpitt after 1 min of startup. Can
be 100Hz.
Serious enough.

That sounds like crystal heating. All of these oscillators can drive
the crystal at various drive levels (depending on resistor and
capacitor values and/or tank circuit tapping) and different crystals
like different drive levels.

A tuning-fork type crystal (e.g. 32kHz watch crystal) is being
overdriven if the levels are as high as a microwatt.

Most HF-range crystals will take hundreds of microwatts to a few
milliwatts of drive.

Lots of the oscillator circuits in old handbooks are designed around
FT-243 crystals, which can take substantially higher drive levels
(sometimes the tube oscillator was putting out several watts) than
"modern" crystals. And even then those handbook circuits overdrove the
crystals to get more power out of the oscillator! By 1950's standards
100Hz of chirp/drift was not a big deal (was probably better than
average for most equipment.)

Tim.