gemfeller
Cave Dweller
Member since June 2011
Posts: 3,797
|
Post by gemfeller on Jan 20, 2020 20:33:45 GMT -5
toiv0 and Starguy, There are two quick identifying methods for polished star diopside. The first is that the rays of the star don't meet at 90-degree angles. One ray is always slightly crooked. The second may or may not be conclusive. Some stones are so heavily impregnated with crystals of magnetite they're attracted to powerful magnets. For those with instruments to do advanced testing, it has a specific gravity (density) ranging from 3.22 to 3.38 and a refractive index of 1.664 to 1.730. It belongs to the monoclinic crystal system and is known to form as columnar crystals.
|
|
gemfeller
Cave Dweller
Member since June 2011
Posts: 3,797
|
Post by gemfeller on Jan 20, 2020 1:33:08 GMT -5
aDave Tommy rockjunquie I just notice the “rock related” component of the RTH Marketplace. The only way this relates to rocks is, beeswax is a component of dopping wax. Jewelers also use beeswax as a "stone magnet" when setting gems. The wax picks up stones and makes it easier to manipulate them into small settings. It releases easily and is steamed away when the setting is cleaned. Facetors also use beeswax to make laps for polishing very soft stones. There are several "recipes" for making them but beeswax is a component in most I know of.
|
|
gemfeller
Cave Dweller
Member since June 2011
Posts: 3,797
|
Post by gemfeller on Jan 20, 2020 1:24:37 GMT -5
Starguy, Nice work. When I started cutting star sapphire the only grinding wheels available were silicon carbide. This was in the old days before diamond wheels entered the scene. On even ring-size stones it was hard to tell which was doing more cutting, the wheels or the sapphire. I remember I cut a little, then dressed the wheel a lot to remove the deep groves left by the corundum.
|
|
gemfeller
Cave Dweller
Member since June 2011
Posts: 3,797
|
Post by gemfeller on Jan 20, 2020 1:18:57 GMT -5
opalpyrexia , my daughter married an Aussie from Victoria. One of his first questions on arrival was "Where are the flies?" We're fortunate to live in an area of SoCal where flies exist but rarely are bothersome. I think that alone made him feel he'd made a great choice in moving here. I think one of the things that really discouraged my venture to OZ was seeing pictures of the fly-netted hats with festoons of corks dangling from the brims to shoo flies away. They're sold at airports now as gag gifts but then they were genuine and necessary mining apparel.
|
|
gemfeller
Cave Dweller
Member since June 2011
Posts: 3,797
|
Post by gemfeller on Jan 19, 2020 17:47:11 GMT -5
Been watching and enjoying. I came very close to heading to OZ to try to mine opal when I was much younger. It was when Andamooka was in its prime, producing some of the most beautiful green/orange opal in existence. I'm glad now I didn't -- the flies, heat, lack of capital and rough frontier life would probably have done me in. I'm happy the series is airing. It will educate consumers about how elusive fine opal is and how difficult it is to mine. Maybe they'll better understand why it's so pricey.
|
|
gemfeller
Cave Dweller
Member since June 2011
Posts: 3,797
|
Post by gemfeller on Jan 18, 2020 18:08:05 GMT -5
I am pretty sure that Mr. Jon Rolf designed the Graves VXL. Diret drive motor, etc. Yes, he licensed his patent to Graves. Unfortunately they've not done a good job of building machines or customer service. Sad story.
|
|
gemfeller
Cave Dweller
Member since June 2011
Posts: 3,797
|
Post by gemfeller on Jan 17, 2020 12:17:06 GMT -5
I started lapidary work by cutting opal in the early 1960s. In those days symmetry was the absolute rule: calibrated ovals, rounds, etc. Yet considering the nature and price of precious opal, I simply refused to force some beautiful gems into those constricted shapes and I started freeforming.
Since calibrated symmetrical mountings were the only commercial option for jewelry then, I learned metalsmithing to set my creations. But when I started cutting agates, jaspers and other stones I fell into the then-current convention of calibrated ovals etc. Again, there were stones with patterns and scenes that defied being corraled into restricted shapes so I started freeforming them.
Over time I realized the truth of the now-trite saying that "the stone tells you how it wants to be cut." Some, like precious opal and fire agate, don't just "tell" you, they shout and demand!
Bottom line, I guess it depends on the stone being worked and the inclinations of the cutter. Both symmetrical and free-style cuts have their place and their fans. I'm glad I learned to cut calibrated shapes because I'm often asked to replace stones in jewelry. It's handy skill to have.
|
|
gemfeller
Cave Dweller
Member since June 2011
Posts: 3,797
|
Post by gemfeller on Jan 16, 2020 1:38:07 GMT -5
My long-suffering wife abides my addiction -- as long as I give her first dibs on any new stones or jewelry. She's done quite well! My only regret is that she can't stand rock shows. I'd love her company but she's only interested in finished bling, although after many years she's now beginning to appreciate the beauty of "raw rocks." But I could never get her near my cutting equipment. The fortunate aspect of her disliking shows is she can't keep track of how much I spend when I go. It all seems to equal out.
|
|
gemfeller
Cave Dweller
Member since June 2011
Posts: 3,797
|
Post by gemfeller on Jan 14, 2020 20:57:09 GMT -5
If I may chime in, I’m interested in the difference between a $200 -$250 sintered diamond wheel and the $80 - $100 Kingsley North wheels? If I may impose.... Maybe this was answered above - I skimmed the thread quickly. Sintered hard wheels have much thicker diamond coatings than the cheaper wheels, about 1/8-inch. And the diamond is heat-sintered into the metal, not just plated. That's what accounts for the difference in price. Sintered wheels last many times longer that simple plated wheels and IMO they're definitely worth the investment. They will last for years even with fairly heavy use. I do a lot of cabbing and I've been running heavy steel-core 60 and 220 grit sintered wheels on my Genie for over 2 years and they cut like new. No problems with the Genie's bearings either so far. I know a cutter who does far more heavy-duty cutting on a Genie with sintered wheels than I do and he's never had a bearing problem.
|
|
gemfeller
Cave Dweller
Member since June 2011
Posts: 3,797
|
Post by gemfeller on Jan 14, 2020 20:39:10 GMT -5
Hi, and thanks for remembering me! I don't have first hand experience with kunzite, though I've watched three stones shatter on my partner's dop and am not going to risk it on anyone's kunzite any time soon. I know of Peter Torranca, Lloyd Forrester, and Matt Dunkle by reputation, and all do excellent work, though I don't know if they will work with client kunzite. micellular , neither do I. That's why I suggested that the OP contact them directly. And it appears no good deed goes unpunished, judging from the OP's last post. I totally agree with QuailRiver about Kunzite as a ring stone, but it's not for me to make decisions for others. It's good to see you here again. Give us an update on what you've been up to. You've come a long way from hand-polishing cabs while waiting in airports for flights.
|
|
gemfeller
Cave Dweller
Member since June 2011
Posts: 3,797
|
Post by gemfeller on Jan 12, 2020 16:22:22 GMT -5
If micellular can't do the work you need, here are some other precision facetors you might contact. Matt Dunkle, mattdunkle@yahoo.com Lloyd Forrester, clearcutgems.com/service.htmlBoth do custom precision faceting. Gemologist Peter Torraca used to do custom work and he's very good. This is his old email and it may or may not still function: ptgems@gmail.com
|
|
gemfeller
Cave Dweller
Member since June 2011
Posts: 3,797
|
Post by gemfeller on Jan 12, 2020 2:09:24 GMT -5
Kunzite is a very tricky gem to cut. It has perfect cleavage in two directions, making breakage a serious possibility. It has to be oriented very carefully by a knowledgeable cutter. Just be sure whatever cutter you choose has experience with Kunzite/spodumene and its nature. Lots of facetors shy away from tackling it, so good communication with your cutter is strongly recommended.
|
|
gemfeller
Cave Dweller
Member since June 2011
Posts: 3,797
|
Post by gemfeller on Jan 10, 2020 23:01:19 GMT -5
It's hard to tell exactly what's happening. With a magnifying glass on my screen it seems the opal's harder than the ironstone in these pieces. I've cut a lot of boulder from various places but usually ironstone of that dark color is a lot harder than the opal. I think the phenolic might be worth a try to keep everything cutting evenly. But boy those disks have gotten expensive! It could be a fairly costly experiment if it doesn't work. Wish I had something better to suggest but I've never run into that problem. Good luck!
|
|
gemfeller
Cave Dweller
Member since June 2011
Posts: 3,797
|
Post by gemfeller on Jan 10, 2020 22:52:02 GMT -5
Going from 80 grit grinding to 400 sanding is far too big a jump. You say you have 4 expando belts but mention only 3. You might consider 100 grit and 220 grit expando belts before you get to 400. They're a lot cheaper than hard wheels if you're able to switch belts easily. A 1000 finish should polish easily if you carefully check for scratches between operations.
|
|
gemfeller
Cave Dweller
Member since June 2011
Posts: 3,797
|
Post by gemfeller on Jan 1, 2020 1:44:46 GMT -5
Quality rainbow moonstone (labradorite) is hard to find. Most comes from India and ordering from there is always a crapshoot. Besides, they prefer to sell cut goods, not rough. I had one supplier for cut RM that offered quality stones but he's no longer selling. If you're interested he has the best I've ever seen but it's $$$. His name and contact info are on file and I can look it up if you wish.
|
|
gemfeller
Cave Dweller
Member since June 2011
Posts: 3,797
|
Post by gemfeller on Dec 31, 2019 21:23:50 GMT -5
Nice stones! Number two rings my bell. I've cut a fair amount of Tiffany and have had no problems with undercutting, but it's a rock, not a mineral. Since it's a mixture of minerals there are bound to be pieces with varying hardness, especially since it occurs in so many different colors/types.
|
|
gemfeller
Cave Dweller
Member since June 2011
Posts: 3,797
|
Post by gemfeller on Dec 31, 2019 1:54:11 GMT -5
It almost seems like a hoax to me. Seems like a hoax to me, too. No way anything 77% oxygen would have survived falling through the atmosphere or being produced by natural processes. The whole write-up reeks of the same sort of unverifiable hyperbole that accompanied the fake red andesine fiasco , complete with Asian sellers supposedly reluctant to sell and not willing to allow independent geologists to do unrestricted verification of the initially inaccessible purported site(s). It's riddled with speculation and hype. I quit reading when I saw that Dr. Peretti's name (Swiss Gemological Institute) was misspelled. That indicates shoddy research if nothing else.
|
|
gemfeller
Cave Dweller
Member since June 2011
Posts: 3,797
|
Post by gemfeller on Dec 30, 2019 22:17:18 GMT -5
serg10 - An acquaintance of mine, Conny Forsberg, is a professional gem cutter in Sweden. While he is a high-level professional I think he might be willing to help you in your own language. I've had limited but very friendly relations with him and I think he might be able to guide you to the equipment you need. It's worth a try. Tell him ROM from GemologyOnline referred you. You can contact him through his website: gemology.se/
|
|
gemfeller
Cave Dweller
Member since June 2011
Posts: 3,797
|
Post by gemfeller on Dec 28, 2019 19:19:34 GMT -5
opalpyrexia , Thanks for the info. You have great skill with computer imagery in addition to your stone and jewelry work. I need to update some of my methods. I'm stuck in the shellac-stick era. I have some of the thermoplastic material but have yet to try it for holding small objects except for stone-drilling. Your tiny pusher is quite clever. I'll have to try to make one. Is stainless hard enough to push silver or does it need to be tempered? I guess I'm asking whether it was filed to shape or heat-forged.
|
|
gemfeller
Cave Dweller
Member since June 2011
Posts: 3,797
|
Post by gemfeller on Dec 28, 2019 15:00:05 GMT -5
Very nice job and a very lucky Linda. I'm curious about how you set the diamonds. Bead setting? I don't see any beads. Some other method? I'm in the mood to do some casting. My shop's too chilly right now to allow me to work comfortably but I'm looking forward to doing some projects I have in mind. I'm thinking of buying an electric melting furnace -- I find torch-melting to be pretty imprecise. What method do you use? Thank you! The stones are flush set. I was going to set them the way I usually do using the "Blaine Lewis" flush-set method with a pusher, but because the metal slopes down from the center of the starfish I was concerned about the pusher slipping and scoring the surface. So I did some light hammer-setting first and then followed through with aggressive pushing at a steeper-than-normal angle. The photo doesn't really show it.
I wish that I had a furnace. I melt with a propane+oxygen torch using a mostly-yellow flame to minimize O2 absorption. As the metal begins to get slushy, I keep checking it with a quartz rod. At the very earliest moment that I detect that the metal feels and/or looks molten, I let the casting machine go.
Nice job on the setting. I'll have to look up the Blaine Lewis method. It must have been "fun" keeping the starfish in place while you were hammering. My melting method is much the same as yours. I also use propane/oxy. I mostly get good results but there are times when I release the caster too soon -- or too late. Hopefully the electric melter will resolve that issue.
|
|