Please help with China charm token. Means or translation. [Resolvido]

Weight-21,73 gramm, Diam-36mm. Help to identify. Thanks

From Cast Chinese Amulets

4.167a

From Sergei Shevtsov - Chinese Coin Amulets

38 mm S3.98

Obverse

San Yuan He Yi - 三元合一

A Triple First, All in One

Reverse

The eight Trigrams

This charm refers to the “three essentials” of the taoist inner alchimy. "three elements become one".

See a brief description HERE

There are some auspicious charms with “三元” linked to “triple first in the imperial examinations”, but it doesn't seem the case for your charm.

Thank you very much!