I continued work on the large sculptural vessel for Chuck and Sarah O' Koon of Louisville, Kentucky. I refined the hemispherical form of the bottom of the 3 foot diameter bowl by using a plywood template, in order to get the form exactly right. The black lines show me where it is high and that I need to focus my effort.
The next step involved using a grinder with a masonry wheel (shown) to smooth out the bumps left by the diamond wheel.
Then comes the long process of sanding and polishing the form. The first step is using this sander with a 36 grit pad.
I switched to an air-powered orbital sander. This gives a very smooth surface, without the swirls that the regular sanders leave. I use the progressively finer grits of 80, 220 and 400 to get the final surface finish.
The polished hemisphere gets a 1 inch hole for the threaded brass pipe that will allow the vessel to drain and will work as a pin to hold the vessel on its base. I've placed a piece of red tape on the drill bit so that I will have the hole at the correct depth. This will help me know that I'm at the right depth for the bottom when I flip the piece over and begin to hollow out the inside. The level on top of the piece will help me keep the hole vertically plumb.
In the tradition of 'restless rocks', the piece is flipped over again.
Using the diamond wheel (shown), I cut out the waste stone from inside the vessel.
Then, repeating the process of the outside, I ground the form of the inside.
This was the progress at the end of the week. I have formed the 'waves' around the edges and the inside and edges have been sanded at the 36 grit level.
Below is a picture from the Dave Matthews concert that I went to this week.
The Clement Mineral museum and Fluorite Dig
When I drove through Marion, Kentucky after taking the ferry across from Cave-in-Rock, Illinois on my birthday (see June 16 post), we saw a sign advertising a Fluorite dig sponsored by Clement Mineral Museum. After checking out their website, we sent in our $40 and signed up for the August 2 dig. The first stop was at the museum. It had lots of great specimens from the collection of B. E. Clement who used to own some Fluorite mines. There was lots of pictures and equipment from the old mining days. There was also a good display of back lit minerals and a UV display. My only criticism is the lack of a logical flow to the main display. The regional minerals were mixed in with minerals from world localities and great specimens were mixed with low-grade material. I would suggest that they separate the regional specimens by mine localities with pictures from the sites to give more 'life' and relevance to the story, move the world localities to another room and separate them by mineral families. Low-grade minerals without significance could be removed to storage - because, ascetically, 'less is more'.
Our guide (and property owner) Bill Frazer, took 5 car loads of 10 adults and 2 kids to the site of 3 abandoned mines -Columbia , Eureka (shown above) and Mary Belle-that were within walking distance of each other. They were located in a wooded area next to a creek. Essentially, the sites consists of the funnel-shaped holes of the caved-in mine shafts and small piles of mine dump rubble (shown).
After hours of sweat drenching and muddy labor, Meg, myself and most of the others had little to show for our effort. This family from Georgia used the only technique that would produce results. Using a pick, the husband pried stones from the rubble pile, while the wife examined them for signs of Fluorite. We had assumed incorrectly that Fluorite was occuring in the ground naturally and that it was to be found loose, like 'floaters' in the ground. However, it can only be found in the piles of rock from the mine.
The Eureka site, which is next to the creek involves a great deal of digging in dirt and mud. The two other sites are dryer and basically entail turning over every rock and breaking open those that show some color.
After moving and examining a lot of stones from the dump pile, they were able to find small pockets that have some Fluorite crystals.
After washing the mud off in the creek, you can see the dark purple color of the Fluorite in the pockets.
This was the best piece that they found (unless they found better, after we left). There is a picture on the museum website of a nice big Fluorite specimen, however, what
we found was loads and loads of limestone with occasional purple streaks. As this is mine tailings, most of the crystals are damaged in some way if they are on the surface of the stone.
Perfect specimens can be found in protected pockets or by breaking open rock with a large hammer.
There was the remains of an old brick building on the hill above the Columbia mine. I believe this was a smelter for refining lead and the trace amounts of silver that are present in the Galena.
Meg found this specimen of Galena in a Quartz matrix. on the hillside below the smelter. Basically, I was unable to find anything of significance. Each of us were allowed to collect a 5 gallon bucket of material, but I couldn't even find enough 'spar' (purple gravel) to fill even half of our allotment.
The highlight of the trip was when the couple from Georgia gave us these specimens of petrified Coral from southern Georgia. I reciprocated by giving them some pearly pink dolomite from Corydon, IN and a small 'thumbnail' of Millerite from Halls Gap, KY