This is how I made it. You'll need a drill machine and a drill, 1,5 mm. (the 1 mm drill got stuck to often)
Tamarind, kettel, round nose pliers, nippers and flat nose pliers. A craft mat to project the table/ workspace, pliers (to hold the tamarind seed in place) and kitchen towel ( to protect the bead from damaging).

Step 1: Eat and Collect

Enjoy eating the tamarind, spit out the seeds and clean them, I have 26 seeds on my chain. (A couple spare ones are handy)

Step 2: Making Holes

Put the paper towel with the seed/bead-to-be in the pliers and drill a hole.

Step 3: Kettel

Place the kettel into the bead. Use the round nose pliers to make an angle of 90 degrees. Use the flat beak and cutting pliers to make the end at a right size to make a circle ending. Now make the circle with the round beak pliers.