Is using glue a secure and professional method for attaching fully drilled pearls and other natural beads to 18k gold jewellery pieces?

Could you provide guidance on a recommended method for carefully inserting them onto the post without using glue?

Here is an example of how the emeralds and carnelians are set onto the posts:

Source: Cartier (from a line called Cactus de Cartier—this specific product seems to be no longer available). Click for larger image.