Glass Beads, used for smooshing up yeast, are stored on the chemical supply shelf to your right as you enter J337, under "G". They come from SIGMA; if the supply is low order more through purchasepath, or if you don't know how to do that, talk to Soumya. There is a local supply in a beaker on the shelf above Dan's bench, which also has a handy 0.3g scoop mentioned in our Smash N Grab protocol. If you use these replenish the beaker if it gets low.
P/N: Sigma, G8772-500G