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- Lay a large Kim wipe and a piece of weigh paper down next to the Bead Maker. Unwrap a platinum crucible and place it on the weigh paper. Pour the powder mix into the crucible. The sample should evenly cover the bottom.
- Pipette 10 µL of 0.172 mM LiBr wetting agent into the center of the sample powder.
- Open the Bead Maker lid and place sample inside the sample holder. The short wide crucible will fit directly; whereas, the tall narrow crucible will need an additional ceramic ring (no longer have these?).
- Close the lid. Double check both indicator lights are on. Press 'On' to start the program. The process will take 12 minutes and the sample is heated in three stages:
- Stage 1:700°C for 2 min
- Stage 2:1050°C for 5 min,
- Stage 3: 1050°C in agitation for 5 min.
- Be prepared to remove the crucible as soon as the timer reaches 0. The material hardens very quickly so be ready with safety glasses, gloves, and the platinum tipped tongs before the final stage has finished.
- With the Pt-tipped tongs, lift out the crucible and swirl the contents around to get the entire sample into one bead. Wear eye protection! The bead is very hot and rapid cooling can cause it to shatter and fly out.
- Place the crucible on its cooling rack. When seated properly the red light behind it will start flashing. When the beadmaker beeps it should be finished cooling.
- Place a sheet of 6x6 weigh paper on the ceramic plate. Take crucible from the cooling rack and prepare to flip it upside down on the paper to extract the bead.gently tap the bottom of the crucible on the ceramic plate until the bead releases from the crucible. If the bead is stuck, tap the base of the crucible at different angles on the ceramic plate gently. Do not hit the rim of the crucible on the ceramic plate. The platinum is malleable and can easily be damaged if too much force is used.
- When the bead is loose in the crucible, tip the bead out of the crucible on to the weighing paper and then put With crucible in hand flip over and give it a firm whack on the weigh paper. The bead should pop off without much resistance. Put the bead back into the vial that contained the flux/sample mixture.
- If there are small pieces of bead left behind you can use your Teflon spatula to try pry it off. Do not use too much force. The platinum is malleable and will get scratched and damaged if put under too much force. If it still remains, make a note of the sample number and inform the chemistry technician. The residue (if any) should come off during the cleaning process.
- Repeat process for all samples.
- Hand off all beads to the chemistry technicians to continue on with the ICP analysis.
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