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[lithicbeads]

Setting rocks aside is a time honored stone cutter tradition. A time comes for all stones is my point of view so I go with my inspiration of the moment.I have  a stream with very big pieces of oceanic chert to show you , spectacular ones , but mid summer is the time. If you like the oceanic cherts now you will be stunned with these boulders. In the interim I have a spot near Darrington with superb pieces of very unusual oceanic chert  in solid red , solid black and solid silver colored.We can get there now most likely and water depth is not an issue. When you would like to go out holler. The coolest hornfels in Washington is up that same road so we should be able to go there as well. The great chert boulders are from the Bell's Pass Terrain if you want to do some reading up .

[bgast1]

Looks good to me. I had someone tell me that on most stones he goes from 1200 straight to cerium oxide on leather. I have yet to try that yet as I haven't finished a cab in well over a week. I was sick and just didn't feel up to going out to the shop. He said optical cerium oxide. I guess that there are differences in cerium oxide but I don't know the differences in how well they polish. I have some from Graves in Florida but it is labeled as their cerium oxide so I have no idea as to the grade. It seems to work well for me though. I have purchased a cab from a master cabochon cutter and I know that he uses cerium and my first comment was that there is just something about his polish. It's not super shiny (it is very shiny) but there is just something about it that makes the cab stand out. Maybe Frank or Lloyd can chime in about this.

[lithicbeads]

There has been a lot of controversy about cerium oxide quality in the last few years. Before  the availability of diamond pads or soft wheels oxide polishes were crucial. Not so much anymore . Rough now is generally not up to the quality of rough of the past , it has more cracks and pits , so oxides are often a problem as they get lodged in the stone and mar it's finished appearance. In addition the diamond has allowed non traditional stones that are not as silica filled to be cut well. Oxides can be deadly fast. They can take a polish a long way quickly but can also be a trap . In the old days we saw many stones with a great polish but inferior sanding. Polish over visible scratches. I have seen this in very expensive stones from Europe ( Idar ) from the late 1800's.
 The speculation in rare earths caused by the Chinese manipulation of the market brought a tremendous run up in some oxide prices and cheaper grades seem to have become the norm. This was a trend before the crisis as well. The purity of the oxide and the type of contaminants are crucial. The optical industry used to use a grade labeled " French " I believe and it could be distinguished by color to a degree. I have seen white , pink and yellow cerium over the years. PH can also make a difference  as either extreme seems to make polishing easier. Traditionally out west acids were used with cerium. Colloidial polishes used a very basic strategy and it seems to have basically gone by the wayside.If you find polish you love reorder immediately after being assured it is identical to the grade you like. The quality due to source and manufacturing process varies with time.