 |
| Sign in or Register Home |
|
|
|
| Buy | Sell | Education | Forum | Directory | Blog | |||
 |
||||||||
|
||||||||
| HOME : FORUM : EDUCATION : GEMSTONES : Lapidary : How I cut a gemstone (modavite pendeloque) |
|
|
|
Thread Tools | Search this Thread |
|
How I cut a gemstone (modavite pendeloque)
Post#1 @
11-21-06
, 12:06 PM
I figured I'd share with you guys some pictures of me cutting a gem stone from start to finish since people have asked how the process works. Keep in mind, the way I cut may be different from others, so this is only one set of techniques, but a lot of the principles remain the same. So, here we go... A bunch of you a beautiful collection of colorful gemstones. I have a box of rocks. LOL. This is all my gem rough waiting to be cut:  I pick out a nice big moldavite chunk:  It's 14cts right now. Remember that number so I can show you how much gem weight gets lost in the cutting process. The goal is to lose as little gem weight as possible, so I take a look at my stone and study it all angles. If this stone has inclusions, now would be the time to shave off the 'dirty' sections. Since this one is perfectly clear though, I don't need to worry about that! I decide on a step pear shape (called a "Pendeloque" in this cutting diagram):  |
|
|
|
|
|
|
|
Re: How I cut a gemstone (modavite pendeloque)
Post#2 @
11-21-06
, 12:12 PM
Before, I begin, I need to affix the stone to a "dop stick" which is essentially a metal rod that holds the gem. Here's my pot of goop...esentially a mixture of hard wax and resin. It's sticky and needs to be heated to melting temperature:  Ewwww. Although pure resin smells good:   Notice I lay the gem on the dop pot as well so that it too heats up. Resin sticks to warm surfaces. The dop stick gets stuck into the melting wax so that it heats up and the substance can adhere to it better. Once a nice glob gets on there, I mush it around the gemstone:  Unfortunately, I didn't get any short of me burning my fingers and trying to get the stone centered, etc. etc. Trust me, with my rudimentary tools, it's a bit tricky! Ta da! It's on the stick! |
|
|
Re: How I cut a gemstone (modavite pendeloque)
Post#3 @
11-21-06
, 12:20 PM
Whoops, I didn't mean to post that pic twice! Anyhow, aside from the faceting machine itself, these are the other tools that are necessary to cut stones with. A set of cutting and polishing discs:  A hand set that controls rotational symmetry and angular pitch. By combining different angles and degrees as defined by the cutting diagram, this is how you get facets cut into a gemstone.  The dop stick sits inside of the handset. Here I am cutting:  The benefit of having a handset is that i can check how much i've cut periodically by picking it up and looking at the stone. Here I've made my first round of pavillion facets. Can you see how they meet in the middle?  I will continute to cut the entire stone with the roughest grit and then recut on a finer disc, also called a lap. Here I've gotten through all the facets with the cutting laps.  The next step is to go through all the facets again with a polishing lap. I pick up the stone and check how even the polish is by looking at how the light reflects against the facet. You can see how some of the facets are shiny and some are still dull do to not being polished all the way:  |
|
|
Re: How I cut a gemstone (modavite pendeloque)
Post#4 @
11-21-06
, 12:25 PM
when I'm done polishing the pavillion, the hardest part comes. Flipping the stone! Notice all gem stones have a top half and a bottom half and normally you cut the bottom half first. I use a "flipper" to help made sure my stone dop sticks are aligned properly because if they're not, the crown and pavillion will be al wonky. You also have the make sure that the pavillion and crown are paralle to each other. I heat a second dop stick much the same way as I did the first one and glop it onto the other side:  Here's what the stone looks like right now:  If I am happy with the alignment, I use a butane torch to soften [i]the first side[i]. This weakens the bond and then I can release the dop stick from the crown. It is imporant to do this only after both sides have completely cooled down because you dont' want to accidentally take off the dop stick from both sides!  The flipped stone:  So, that's what I have so far. I'll keep you guys posted, but cutting the crown is really similar. I'll upload pics of the finished gem here too. |
|
|
Re: How I cut a gemstone (modavite pendeloque)
Post#5 @
11-21-06
, 12:50 PM
Interesting Briolette! What kind of handpiece is that? Being a lefty with a right handed machine must be a bit of a PITA. It's a good thing that you've got a removable handpiece so you can get to the angles easily enough. I use a Facetron right now and I can't imagine trying to use it if I were left handed. You don't show your polish lap too clearly. Do you have a BATT lap ? Mine gave me fits at first, but I kept monkeying around with it and love it now...very fast even on sapphire. I'm looking forward to seeing the end result on this stone, looking GOOD so far! |
|
|
|
|
Re: How I cut a gemstone (modavite pendeloque)
Post#6 @
11-21-06
, 01:06 PM
Great post, briolette! Looking forward to the next segment :-) |
|
|
Re: How I cut a gemstone (modavite pendeloque)
Post#7 @
11-21-06
, 01:15 PM
thanks itbit. MichaelE, I use a Raytech shaw faceting machine. Oddly, because I learned to cut left handed (come to think of it, my teacher was left handed, so I guess that's how that happened LOL), it does't bother me. I'm actually a righty! The good thing is that the turn table goes both directions...as for polishing lap, I'm using a vargas pol-a-gem cerium oxide one since I usually cut softer stones. In fact, I don't I've ever cut anything harder than a spinel before. I do have a BATT Lap though, brand new and still in the box. What kind of polishing compound do you use with it? I find it odd that the surface is so nubby and textured. I'm used to only seeing laps that are scored. I take it that you would use diamond boart with it? Does it polish as well as a zinc lap or better? |
|
|
Re: How I cut a gemstone (modavite pendeloque)
Post#8 @
11-21-06
, 01:28 PM
Quote:
I use diamond spray since it's so well dispersed in the liquid. I use two Batt laps, one at 3000, (prepolish), and one at 100k. I use these laps for all materials and just use a lighter touch or a more viscous liquid to polish softer gems. The tin in the BATT is very soft and sucks up diamond, (like boulders in mud on a microscopic level). Once the lap has been used and is well charged you can vary the distance that the stone is in contact with the diamond by varying the viscosity of the polish liquid used as well as the speed of the lap. For softer materials I use WD-40 and a spritz of glass cleaner to make a thin white emulsion on the surface of the lap, turn the speed down and use a light touch. It's fast and I have few problems with cat hair scratches. I've never used zinc, but it's awfully hard and so wouldn't absorb the diamond particles as well, (one of the benefits of tin laps is that larger pieces of diamond polish eventually get shoved down into the lap far enough that they act like smaller and finer polishes). Oh I forgot to add, don't score that Batt! You want the suface to level itself out and the diamond polish to embed itself in the surface and scoring is a waste of time and make the laps noisy. |
||
|
|
|
Re: How I cut a gemstone (modavite pendeloque)
Post#9 @
11-21-06
, 01:35 PM
Quote:
Ahh, I see. I should try changing the viscosity of the polishing liquids. That seems like a much more cost effective technique than having a whole bunch of different types of polishing laps to take care of different gem materials. |
||
|
Re: How I cut a gemstone (modavite pendeloque)
Post#10 @
11-21-06
, 01:51 PM
Wow briolette!!! You talented woman you!!! That's really cool to see the process!! I can't wait to re-read that all! Karma for that!!! |
|
|
Re: How I cut a gemstone (modavite pendeloque)
Post#11 @
11-21-06
, 02:28 PM
ULTRA COOL pics briolette!!!!!!!! Wow.. most of that whole conversation between you and michael in the posts above looks like Charlie Brown language to me.. "  blah, blah..... blah..... blah.....blah, blah.......blah...... "  You guys lost me way back there!But the pictures I get! I love seeing how it's done! Thanks so much for showing us. And I'm looking forward to seeing the finished gem! 
|
|
|
|
|
Re: How I cut a gemstone (modavite pendeloque)
Post#12 @
11-21-06
, 03:32 PM
Cool, can't wait to see the finished stone!!! |
|
|
Re: How I cut a gemstone (modavite pendeloque)
Post#13 @
11-21-06
, 03:43 PM
Wow thanks for the backstage pass briolette! You're clearly a ver talented lady. I can't wait to see the finished product 
|
|
|
Wow
Post#14 @
11-21-06
, 03:57 PM
Woohoo thanks so very much for posting this info! I love love love both diamonds and gemstones, obessed really I have a few hundred in my collection waiting to be set. I'd love to know where I could go to learn what you know and also how to set gemstones too! Wow you are soo gifted I can't wait to see the rest of this process! |
|
|
Re: How I cut a gemstone (modavite pendeloque)
Post#15 @
11-21-06
, 04:09 PM
Totally cool Briolette! I love learning new things especially on my favorite topic. Thanks for giving us an inside view into what you do! And thanks for the link from your old thread! Karma for that!!!! |
|
|
Re: How I cut a gemstone (modavite pendeloque)
Post#16 @
11-21-06
, 04:39 PM
thanks everyone! I certainly have tons of fun cutting stones and it's a n addictive but fulfilling hobby. Quote:
Bila, my university has a gem identification class through the geology department and it has a lapidary component through it. However, if there's a gem society or Rock Hound club in town, they'll usually have people you can learn from. You could teach yourself. The book I use is "Faceting for Amatures" written by Glenn and Martha Vargas. They're the ones who helped teach the class I took and the book is well written and easy to understand. Aside from the faceting machine, the rest of the equipment is pretty simple. MichaelE and Gene (precisiongem) are both master lapidaries and frequent these boards. I'm always willing to help, so I'm sure you can get tips and tricks easily if you want to start cutting. As for gem setting, i really want to learn that as well...and jewelry fabrication too...heck, I just want to be a jeweler one of these days. |
||
|
Re: How I cut a gemstone (modavite pendeloque)
Post#17 @
11-21-06
, 05:55 PM
haha I think you and I both want to be jewelers God knows my husband would love it if I knew how to do real gemstone setting and setting casting! I made some earrings and a necklace set for my best friends wedding last year. It was the jewelery for the bridesmaids and I made it with a prong compression tool. It was good for a beginner but not well long lasting quality, like doing it the regular way with a torch. But it did the job. I will have to post some pictures of it now that i have a decent digital camera. Thanks so much for the information about the unveristy I did not think of that. We live in the pacific northwest and I will have to see if U of W has a good geology program and a class where I could learn some gem setting. Hubby has offered for me to go back to school now that we are in a better place financially but now with a new baby I think the only classes I will have time for are ones I can do online. I have been looking at the GIA online program just to bulk up my knowledge and deepen my obession lol..not like I really NEED anymore encouragement but its good to have the knowledge on hand in case you need it. Oh and thanks for the info on the book too can I get it on Amazon.com or do I need to look at a speciality jewelery store? THanks again... |
|
|
Re: How I cut a gemstone (modavite pendeloque)
Post#18 @
11-21-06
, 06:35 PM
I think a lot of rock shops carry it. You can get it on Amazon, but it looks like they are out of stock. There are many other faceting books out there too. GIA has nice web classes. I'm really impressed with their interface and how quick I got my assignments back (I got my AJP through GIA). Everything was so organized, but to be honest, the full color, gorgeous photos of gems and jewelry in the text were what really excited me! |
|
|
Re: How I cut a gemstone (modavite pendeloque)
Post#19 @
11-21-06
, 06:58 PM
Quote:
Bila75, Here's a list of jewelry trade schools: http://www.colored-stone.com/links3.cfm It looks like there's a trade school in Portland, OR. I would also look at your local Community Colleges as they often have a local pro teaching stone setting, gem cutting and so forth. |
||
|
|
|
Re: How I cut a gemstone (modavite pendeloque)
Post#20 @
11-21-06
, 07:41 PM
Briolette this thread has been quite educational and "fascinating"(pun-intended). Although much of it went over my head, it makes me want to check into a lapidary course! I can't wait to see the final result of this beauty. How long did it take you to cut the bottom half of the stone from start to finish? Now I am familiar with what Michael goes through when he cuts his amazing stones! Really Cool!~Ronda |
|
|
Re: How I cut a gemstone (modavite pendeloque)
Post#21 @
11-22-06
, 10:49 AM
Glad it is of interest. I probably should have gone into more details, but then it might get a little rambly. I'm also terrible at typing. :P Anyhow, I'm rediculously slow and like I said my machinary is rinky tinky close breaking. I think I'm the 4th owner of my cutting laps. LOL. Seriously. Cutting often depends on the diagram and the hardnes of the stone, whether you mess up in the middle and how accurate your machinery is. For this one the diagram is fairly simple. I've been working on this stone off and on during weekends for a while. I think it total, for this stone, it took me about 8 hours from dopping to cutting and then 2 hours to get a nice polish. That doesn't count time to let the stone cool off and "set up" in the wax. The time consuming part is recutting facets with the finer laps to get large scatches out and if you space out, you sometimes over cut and have to recut the whole thing from the beginning if you want the facets to meet correctly. Anyhow, off to bake some cranberry muffins. Have a great Thanksgiving tomorow, everyone! |
|
|
Re: How I cut a gemstone (modavite pendeloque)
Post#22 @
11-22-06
, 11:14 AM
Way to go Briolette! Keep posting, this is a fascinating and educational thread. Looking forward to more......
|
|
|
|
|
Re: How I cut a gemstone (modavite pendeloque)
Post#23 @
11-22-06
, 07:56 PM
Thank you Bri for that tutorial. Awesome shade of green on the moldavite too. |
|
|
|
|
Thank you!
Post#24 @
11-23-06
, 03:18 PM
Thanks for the information Micheal E! Its definatly something I will be looking into next year once I have the time to get out of the house. But I will definatly look into the community colleges and other trade schools around here there are quite a few and you're right maybe there is an expert teaching classes on the side? Briolette, Thanks again for starting this thread! Its so awesome to be able to share and learn from one another! Keep up the great work! Happy Thaksgiving everyone! Bila75 |
|
|
Re: How I cut a gemstone (modavite pendeloque)
okey dokey, more on my moldavite...I finally got the chance to finish cutting the crown of the stone and wow...she's a bute. Only one small over-cutting mistake this time around that I was pretty much able to fix (although I had to recut a lot of the stone. Sigh).And, she sorta looks like a christmas tree. Imagine that! |
|
| Read Messages in: | Lapidary | All forums | ||||
| Newer: |
|
|
||||
| Older: |
|
|
| Thread Tools | Search this Thread |
|
|
| Contact Us - Guidelines - Privacy Policy - Refer a Friend - Top^ |
|
|
|
