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Home » Tumbler Rough » Lake Superior Agate Rough
Lake Superior Agate Tumbler Rough
| This is a photograph of our Lake Superior Agate rough. This material consists of agate nodules and pieces between 1/4" and 1" in diameter. Lots of red, white, gray, orange, brown and crystal color material with nice banding and occasional eyes. Photographed wet to show full color. See photograph of polished material below. |
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Lake Superior Agate
Lake Superior Agate is widely known as a tumbling rough. It is so popular in the Great Lakes area that the Minnesota legislature designated it as the official "state gemstone".
Lake Superior Agate is typically a banded material - often concentric - but sometimes has eyes and mossy patterns. The red, yellow, orange and brown colors are a result of an iron pigment within the agate material.
Our Lake Superior Agate mix consists of small nodules and nodule fragments found in the Great Lakes area. It is a tough, dense material in pieces that range from 1/4" (6 mm) to 1" (25 mm) in size. It takes a great polish.
We use TXP polish - an aluminum oxide compound - when we polish Lake Superior Agate.
The rough above was photographed wet to show full color. A photo of some finished Lake Superior Agate that we polished is shown below. |
This photo is of a batch of Lake Superior Agate rough that we polished. It is a very hard material that can take an absolutely brilliant polish. Our tumbles had plenty of bands, quite a few eyes, a little moss, several crystal windows and lots of red, orange and brown colors. Here are the steps that we used to achieve this polish.
Steps 1A, 1B, 1C: We loaded a little over four pounds of rough into the barrel of a Lortone QT6 tumbler with 60/90 grit silicon carbide and tumbled for three weeks. The nodules had some rough husks and the broken pieces had some deep dimples so we knew that we would run more than one week in 60/90 grit to get the really nicely rounded tumbles that we like to produce. At the end of Week One we rinsed the nodules, picked out a few that revealed cracks or porosity and loaded the rest back into the barrel with fresh 60/90 grit. At the end of Week Two we rinsed and reloaded with fresh 60/90 grit and ran for Week Three. That's three weeks total in coarse (60/90) grit.
Step 2: We loaded the agates into a single barrel Lot-O-Tumbler and ran for two days with 150/220 grit, rinsing and adding new grit every 24 hours.
Step 3: We then ran two days in the Lot-O-Tumbler with 500F grit prepolish, rinsing and adding fresh grit after 24 hours.
Step 4: The final step was just 24 hours in the Lot-O-Tumbler with TXP aluminum oxide polish. Burnishing was not needed. Wow!
We were amazed at how brightly they polished in just one day.
Total processing time was three weeks, five days. |
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Large Ceramic Media:
Large ceramic pellets work great as a filler and for delivering grit or polish to difficult-to-reach surfaces. More information... |
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Small Ceramic Media:
Small ceramic pellets work great when you need small material for better tumbling action or to deliver grit or polish to difficult-to-reach surfaces. More information... |
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Plastic Media:
Use plastic pellets to cushion fragile stones when tumbling in a rotary tumbler. More information... |
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