BMW broken quartz, which frequency?

[Belloriccoefamoso]

Hallo
i have a key with a broken quartz like in photo
unfortunately i didn't found the surface where is written frequency
can someone help me?
thank you
336178336179

[Belloriccoefamoso]

could be 13.560?
is a 4 pin version
the measure of quartz is (mm.) 3.2 X 2.5

[Belloriccoefamoso]

and another question: the orientation of the quartz?
i know have 2 pin for alimentation +/- and 1 for oscillation but the surface was destroyed...

[Belloriccoefamoso]

noone have ideas?