metalsmith
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Post by metalsmith on Jan 18, 2017 13:50:31 GMT -5
Drill n' tile SiC / diamond file or cut a slot with a dremel diamond wheel Alternatively buy a square drill-bit
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metalsmith
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Post by metalsmith on Jan 18, 2017 13:20:19 GMT -5
Thanks for the ideas - keep 'em coming!
I have diamond blades and can achieve a couple of mm kerf.
I only have the one piece of really good material, but I'm just micro-slabbing a rough sample, hoping to get a slabette around 1mm thick. Some of the left over will be the white stuff that I can thin right down to approx 1mm and then use to trial any of the more creative methods.
I wondered about thin copper wire run thro' diamond dust and setting it as a saw blade in a piercing saw. It might be worthwhile just trying a piercing saw and seeing if it gets any gain. At 1mm thick there's not much to get through.
6mm is definitely more than I can lose. The utility knife idea might just work. Come to think of it, I also have a modelling saw that can cut soft metals and might just stretch to lapis.
Facetters are few and far between here in the UK. A facetting saw might be on the horizon but that's a long way off for the present.
Thanks again for your ideas. Any more?
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metalsmith
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Post by metalsmith on Jan 18, 2017 8:09:15 GMT -5
I set quite a high malachite cab using a relatively low bezel with the effect that the belly (to continue the muffin-top analogy) weight pulled the pendant forwards. I had thoughts along similar lines where with a grooved cab, the stem of a _|_ (viewed in cross-section) could be fitted in the groove, with both ends _ and _ (left and right, respectively .... haha!) running up and down the cab. TBH tho' it would be recommended more highly to get the cab in proportion rather than having to deal with the consequences.
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metalsmith
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Post by metalsmith on Jan 18, 2017 7:51:05 GMT -5
Hi, I have a very thin (1mm) piece of lapis that I've been thinking about for a few months, as you do. Now I've finally found inspiration for the design of it, the off-cuts could be useful if they were viable. The difficulty lies in cutting the lapis (single straight line) with a non-existant thickness of cut. Noting this is not possible - with the exception of simply breaking it and hoping the fracture follows my desired cut-line (unlikely)... What is the very thinnest thing I could cut it with? Any thoughts would be welcome including blue-sky thinking. Thanks Chas
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metalsmith
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Post by metalsmith on Jan 18, 2017 7:44:52 GMT -5
I've actually had great success drilling wholes. Are you ready for this southern ingenuity?? I make my own molds (100% silicone & cornstarch) to hold the stone securely and put box tape on the back. Do you consider the back support to be the source of your success? Presumably that prevents blowouts just as would happen with splintering on drilling wood.
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metalsmith
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Post by metalsmith on Jan 17, 2017 17:16:11 GMT -5
Some seriously nice cabbage here! Some nice cabbage, a couple of wonderful spuds and amazing parsnip. No turkeys!
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metalsmith
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Post by metalsmith on Jan 17, 2017 16:56:13 GMT -5
Beautiful banding looks promising to me all right!
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metalsmith
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Post by metalsmith on Jan 17, 2017 16:42:24 GMT -5
I believe fractures show up due to the vibes of polishing opening pre-existing lines of weakness. 3000 might just do it (has for me on chrysocolla) but coarser wheels definitely will. My rule for larimar is to use nothing more coarse than 600.
Great cabs and wraps.
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metalsmith
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Post by metalsmith on Jan 15, 2017 17:24:00 GMT -5
it posted! Sweet wrap: very nice, well done!
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metalsmith
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Post by metalsmith on Jan 14, 2017 10:02:07 GMT -5
I suggest the best approach may be to set the jade grains and then polish them whilst set in the ring.
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metalsmith
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Post by metalsmith on Jan 14, 2017 9:59:05 GMT -5
No relevant jasper... maybe I'm out of the picture on this one. Noting the abstract design on rivarat submission so far, I may just have a chance of finding something. Nice one rivarat!
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metalsmith
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Post by metalsmith on Jan 14, 2017 3:13:10 GMT -5
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metalsmith
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Post by metalsmith on Jan 13, 2017 14:06:24 GMT -5
More obsidian info, rocks and knapping fun here
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metalsmith
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Post by metalsmith on Jan 13, 2017 3:12:10 GMT -5
@shotgunner Ahh... you got carried away with states of matter, I see! In a quantum spin you may be. Dangerous, it is to play with neutron-degenerate matter... Neuron degenerating it can be! You must unlearn before you can learn. Superfluid with zero viscosity (or infinite fluidity; i.e., flowing without friction), was discovered in 1937 for helium, which forms a superfluid below the lambda temperature of 2.17 K. In this state it will attempt to "climb" out of its container. It also has infinite thermal conductivity so that no temperature gradient can form in a superfluid. Placing a superfluid in a spinning container will result in quantized vortices. A quantum vortex “carries” quantized angular momentum, thus allowing the superfluid to rotate; in a superconductor, the vortex carries quantized magnetic flux. Scotty, we need more power!
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metalsmith
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Post by metalsmith on Jan 12, 2017 17:34:09 GMT -5
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metalsmith
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Post by metalsmith on Jan 12, 2017 13:57:50 GMT -5
The red is (I gather) iron infusion (is that the right word?) from the edge of the boulder. Infusion, effusion, diffusion, pick one, it's still gorgeous! My mineral-monitoring AI system reports a spike in global Dumortierite demand as a result of this post!
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metalsmith
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Post by metalsmith on Jan 12, 2017 13:48:59 GMT -5
metalsmithChas that was amazing! Clicking links soon. And you have me an idea to test a product. ETA: re toffee analogy Obsidian isn't often clear. Therefore, I suggest toffee must not necessarily be either! Haha! Must learn toffee better to understand plutonics!! No problem. Not all toffee is clear. Not all glass is transparent; I found a paper where the crystal content of obsidian was stated as ranging between 5-15% for one locality. Glass is more of a phase description, seemingly not fitting with any of solid liquid or gas: leads me to this. More links! Read Glass through Liquid Crystal States - it's all relevant. For the geochemical composition, search on what constitutes rhyolite - it's the same stuff (generally!) Enjoy!
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metalsmith
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Post by metalsmith on Jan 11, 2017 15:33:30 GMT -5
blah, blah... The example case of a different glass - toffee - should illustrate the compositional argument well. Cryptocrystalline fudge, it could be said is completely different to toffee. In fact, leave it too long and it crystallises out; some call that fudge too. At a microscopic level, the composition of the melt has changed certainly, but boil it all up again and toffee, it can be once again. Coincidentally I found this!blah, blah... 'Cept they're wrong ... 'This is like a volcanic igneous rock that cooled quickly above the earth’s surface, like obsidian.' No, the metaphorical equivalent of that would be hard, clear, glassy toffee!
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metalsmith
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Post by metalsmith on Jan 11, 2017 15:26:39 GMT -5
Yes, obsidian can have a granitic composition. Normally it is basaltic. NB the terms 'Granitic (continental / SiAl)' composition and 'Basaltic (oceanic / SiMa)', are the two root-families of igneous geochemistry. This is an assignment of the melt species at a family level. Recall the basic paradigm of classification involves a level of generalisation. As per usual, the scale of the claim was macroscopic where the scale of examination here tends to the microscopic. Not knowing how much the source of the statement knows, it is tempting to say they were wrong. Of course there are often exceptions. vegasjames suggestion for inequality appears to stem from the point of view that it can't be the same due to the different granularity. Note that for obsidian, we're talking about glass. Glass is by definition out of equilibrium (and instead, equalibrated with the conditions at the time of formation. Even the term cryptocrystalline can be erroneous since the melt is quenched. Strictly speaking it often remains a fluid. In the UK there are very old church (etc) windows that have flowed so the bottom is thicker than at the top. However it still hasn't crystallised. The example case of a different glass - toffee - should illustrate the compositional argument well. Cryptocrystalline fudge, it could be said is completely different to toffee. In fact, leave it too long and it crystallises out; some call that fudge too. At a microscopic level, the composition of the melt has changed certainly, but boil it all up again and toffee, it can be once again. Coincidentally I found this!Composition varies all through the pluton with a 360 degree basis of variation; think to the occurrence of inclusions in crystals; reaction with the host rock, xenoliths, heat / cooling and pressure / release. It could be said that the first eruptive material to blow out of a volcano is different to that in the pipes behind it and the pluton otherwise it wouldn't have blown out first. It may be the petroleum from the crude, but generally not so well fragmented, noting the timing of magmatic ascent can be very rapid. However, as soon as the blow-out occurs, a huge change is initiated due to the change in pressure and particularly the hydrous phases and viscosity. Donald Dingwell ran a course on Volcanic Eruptions on Coursera (it's not there now, but may be again in future if you're interested - but *warning* ... the geochemistry and for me, at least, the visco-elastic relationship of structural relaxation was a head-scrambler). The essence of his delivery can be found here .
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metalsmith
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Post by metalsmith on Jan 8, 2017 15:42:25 GMT -5
Goshenite, but yeah, same difference. That's just about cuttable! Goshenite is colourless beryl? Yes? No? This is colourless aluminium oxide. Sapphire? No? I'm cornfused. It seems you correct me. I'll blame my error on being under the weather.
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