Think you have a tough job?
From the website of the Hawaiian Volcano Observatory (USGS):
Hawaiian Volcano Observatory geologists get fresh lava samples as close to the vent as possible. Once the sample is scooped from the pāhoehoe lobe, it is quickly quenched in a bucket of water to stop the growth of any crystals and to preserve the composition of the liquid lava. Once cooled, the sample is sent first to UH Hilo for quick analysis of a few components and prepared for a fuller analysis of its chemical components by a lab on the mainland. These data are used, with HVO’s geophysical monitoring data, as another way to assess any changes that may be occurring within Kīlauea volcano.