Lethal Lead and Silly Salt

2/22/13

Today I started off my internship by cleaning out a sphalerite capsule from last week. I extracted the sulfur 34, but there as still a lot of sulfur stuck to the sphalerite mineral. I put the mineral in a beaker with some ethanol and placed it in the ultrasonic cleaner which sends ultrasound waves through the water to try and break up the sulfur on the mineral without damaging or scratching it in the process. While the sphalerite was being cleaned, Heather and I looked at the polished barite minerals that were still attached by crystal bond to a metal disk. After singling out a crystal with the smoothest surface, I carried the disk over to the hot plate. After the crystal bond had softened, I extracted the desired crystal and put it in a beaker with ethanol where it joined the sphalerite in the ultrasonic. While we waited for the ultrasonic to remove the crystal bond from the barite, Daniele, Heather and I went to the furnace. Barite is a softer mineral and not too many experiments have been done with sulfates so we decided to run our experiment at a low 300 degrees Celsius and to take the experiment out on Monday to ensure the sulfur wouldn't travel all the way through the barite before we took it out. After finding a furnace that was pretty close to 300 degrees we headed back to the lab. Daniele had to go to a conference call, so Heather and I looked at some of the other barite minerals under the microscope. We took some really cool pictures on Heather's phone and I hope to be able to put those up when she sends them to me. However, Heather did send me a picture last week of a capsule right after she took it out of the furnace.

As you can see, the sulfur is a reddish color when it comes out of the furnace! Usually it's a lot more red, but it has already started to cool in this picture. After looking at the barite minerals under the microscope, we filled a capsule with our desired barite mineral and some recycled sulfur 34 along with some new sulfur. We evacuated the capsule using the vacuum and while we were waiting, went to check on the furnace one last time. By the time we got back, our tube with the sulfur and barite was ready to be capsulized! Heather complemented me on my speedy efficiency as I quickly melted the tube to form a vacuum sealed capsule. We then placed the capsule in the furnace. With some time to kill, Heather took me to the room across from the lab where a lot of the pressurized furnaces are kept. We looked at some big metal tables that had been made in the workshop and were being sanded down. Apparently some of the soldering had some lead in them so we tried not to breathe too much. Heather showed me some salt that a mechanized mortar and pestle was grinding This salt will be pressurized into solid tubes which are used in the pressurized surfaces. An electrical current heats up the sample while the pressurized furnace simultaneously exerts a force upon it. The salt cells help to distribute this pressure fairly evenly throughout the experiment. The electrical current helps to make the salt soft, which helps to make sure the entire area surrounding the experiment is pressurized. Next week, we are going to look at some data from a former sphalerite experiment along with clean out the barite capsule. I'll try and put up some of the pictures I took today as soon as Heather sends them which will hopefully be before then.