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Author Topic: What to expect inside this agatized coral, and how to cut it?  (Read 323 times)

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R.U. Sirius

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What to expect inside this agatized coral, and how to cut it?
« on: October 02, 2020, 09:31:11 PM »

I've been wanting to start sawing this one, but hesitate as I have no idea what to expect, and wouldn't want to ruin it. The white (opalized?) crust shows round features with radial rays on what I would call the top and the bottom. Straight columnar features are then apparent on the sides, running from bottom to top.

The whole stone is  feels heavy and solid, so I don't expect large cavities, if any.

Several small chips in the crust only reveal featureless, hazy agate.

My current best bet is to cut it perpendicular to (across) the presumed columns, however this would produce short and wide slabs. Can anyone point me to examples of patterns revealed by different angles of sawing similar stones?


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Re: What to expect inside this agatized coral, and how to cut it?
« Reply #1 on: October 03, 2020, 11:12:43 AM »

Sure, I'll post pics in a couple minutes as I will need to take a couple pics.  Your understanding of the outcome is right on though.  Just like petrified palm wood or palm root cut parallel to the growth lines and you expose the length of the coral and it has a unique look but not one that I am personally fond of.  I much prefer perpendicular to the growth lines which on most Corals gives you the look of sliced oranges.  There are design cases for cutting both ways I just gravitate to the orange slice look.  I am sure either Jhon or sandsave or maybe even ryalydog has posted a coral sphere. 

One note is the color of your coral, when all monotone colors are present the effect is much less than in coral where the polyps are actually different colors or at least good contrast change.  However in you 2nd pic in the center it looks like the center of your coral is going to change darker which is great.  The same goes for calcite stalactites from mines including Kokoweef, once you are in the whites it loses a lot.  I haven't tried doing any sort of color change technique like heat or i think sugar? baking.

There are also corals unlike what you have that have wild patterns no matter which way you cut like those from brain corals.  Ill post pics in about 10 minutes.

Pic 1 is cut parallel to coral growth length
pic 2 is an angle cut maybe 30 degrees which lengthens the polyps I wasn't that thrilled with the outcome
pic 3 is a muted coral mid size polyp but still more color than some
pic 4 is brain coral, I have only gotten one chunk of this and LOVE it's patterns!
pic 5 is small polyp coral very monotone tans but patterns are great, I can get 6 polyps in an 8mm x 12mm
pic 6 is the larger polyp and much higher color, this is a much lower percent of average in the corals.

You can see from the parallel cut that depending on the stone those patterns can work well too just depends on what look you are going for.


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Re: What to expect inside this agatized coral, and how to cut it?
« Reply #2 on: October 03, 2020, 09:35:21 PM »

Nice array of photos!  The brain coral is really something special; I will need to keep my eye out for that material. 


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Re: What to expect inside this agatized coral, and how to cut it?
« Reply #3 on: October 04, 2020, 09:38:20 AM »

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