kouma
off to a rocking start
Member since November 2021
Posts: 15
|
Post by kouma on Nov 22, 2021 13:15:22 GMT -5
Hello all, I have a question about a Larimar nodule I recently purchased. This was cut in half but was not polished, it is rough. Here is a picture of it wet, which looks good. However, once it dries up it doesn't look as nice and as blue. As a collector, do you recommend I leave it as is? or you recommend I polish the face of it? If you recommend polishing it, is there an easy process to follow (no machinery) without damaging the stones that I can do at home? I appreciate your feedback. Thanks
|
|
|
Post by Starguy on Nov 22, 2021 13:35:20 GMT -5
Hi kouma Welcome to RTH. Your Larimar is spectacular. Thanks for showing it. Polishing flat pieces is difficult without machinery. Polishing rocks is similar to wood. You use progressively finer grits until you you achieve the finish you want. Larimar is relatively soft so hand sanding may work but it’s tough to find sandpaper much finer than 600 grit. Most people polish rocks to 14,000 grit or even to 50,000 or 100,000. If you attempt it by hand you will want to use a wet method to keep down dust that you don’t want in your lungs. There are machines to polish flat surfaces but they are rather expensive. If you could find somebody with a vibratory flat lap, they might be willing to do it for a fee. Good luck. Beautiful pieces. I’m interested to see what you do with them. Here’s what Wikipedia says about it. link
|
|
|
Post by MsAli on Nov 22, 2021 13:59:09 GMT -5
That's a stone that can be difficult. Might be better seeing if there is someone nearby that can help you
|
|
kouma
off to a rocking start
Member since November 2021
Posts: 15
|
Post by kouma on Nov 22, 2021 14:01:48 GMT -5
That's a stone that can be difficult. Might be better seeing if there is someone nearby that can help you I spoke to a local jewellery shop and they said their Gem polishing guy will charge over a $1000 to polish this, which is ridiculous.
|
|
|
Post by MsAli on Nov 22, 2021 14:04:51 GMT -5
Good lord that is ridiculous
Where are you located?
|
|
kouma
off to a rocking start
Member since November 2021
Posts: 15
|
Post by kouma on Nov 22, 2021 14:06:48 GMT -5
Hi kouma Welcome to RTH. Your Larimar is spectacular. Thanks for showing it. Polishing flat pieces is difficult without machinery. Polishing rocks is similar to wood. You use progressively finer grits until you you achieve the finish you want. Larimar is relatively soft so hand sanding may work but it’s tough to find sandpaper much finer than 600 grit. Most people polish rocks to 14,000 grit or even to 50,000 or 100,000. If you attempt it by hand you will want to use a wet method to keep down dust that you don’t want in your lungs. There are machines to polish flat surfaces but they are rather expensive. If you could find somebody with a vibratory flat lap, they might be willing to do it for a fee. Good luck. Beautiful pieces. I’m interested to see what you do with them. Here’s what Wikipedia says about it. linkThank you Starguy for the quick response and the positive feedback. That picture was while the stones were wet; unfortunately after they dry up, they look very pale. Polishing is supposed to maintain that look of "wetness". I looked at some vibratory flat laps and they are indeed expensive. I wouldn't mind doing it by hand even if it takes hours over several days, which I believe it safer on the stone than using a rough machine. Which grit sizes do you recommend for this type of project and is there a manual for how to polish using the "wet method" that you suggest? Total noob here
|
|
kouma
off to a rocking start
Member since November 2021
Posts: 15
|
Post by kouma on Nov 22, 2021 14:09:03 GMT -5
Good lord that is ridiculous Where are you located? Hamilton, ON Canada. I am about an hour from NY, Buffalo though
|
|
|
Post by knave on Nov 22, 2021 14:09:54 GMT -5
You can get a flat piece of stainless steel or iron, and make a slurry with each grit (60/120/600/1200/6000/etc) mixed with water Be careful to clean the surface completely between grits.
|
|
|
Post by MsAli on Nov 22, 2021 14:10:54 GMT -5
greig any suggestions of where they can take it
|
|
kouma
off to a rocking start
Member since November 2021
Posts: 15
|
Post by kouma on Nov 22, 2021 14:20:35 GMT -5
You can get a flat piece of stainless steel or iron, and make a slurry with each grit (60/120/600/1200/6000/etc) mixed with water Be careful to clean the surface completely between grits. I am trying to imagine what you are suggesting, are you able to provide a video or a link for step-by-step instructions?
|
|
|
Post by parfive on Nov 22, 2021 14:41:33 GMT -5
re: hand polishing
Try a test run before you empty your supply of elbow grease. Beg, borrow or steal a teaspoonful of aluminum oxide polish and sprinkle some on a piece of denim. Dry. Rub one of the flat faces on the rag, vigorously, for about ten or twenty seconds and see what ya got.
If you like what you see, then you can get some fine grits and do a better job on a piece of glass. Wet. Which grit you start with will depend on how true the cut faces are to begin with.
|
|
|
Post by parfive on Nov 22, 2021 14:59:41 GMT -5
If you decide to go ahead with it, you can polish both halves for double the work or polish just one and admire/show off what a difference ya done did. : )
|
|
|
Post by Starguy on Nov 22, 2021 16:54:09 GMT -5
koumaThere is no manual that I know of. From your photos it looks like a pretty smooth surface. If there are big saw marks or breaks near the end of the cut, I would say weeks or even months of hand work to get it through 600 grit. The wet method is not difficult. Buy sandpaper that is made for wet sanding. Your local hardware store will have it. Keep it wet. I think pectolites are similar to asbestos, having a fibrous structure. You don’t want to breathe that into your lungs. Once sanded and polished they will be safe. If you don’t mind a curved surface on the cut faces, a good lapidary artist could probably help you. Another method would be to pour a decoupage epoxy over the surface. That will maintain the wet look but will be a pain if you want to do something different in the future. Incidentally, I have a big piece of Larimar somewhere. I rounded and polished one end. I don’t think it’s as nice as yours but I bought it in the Dominican Republic for 20 pesos. That was like $3 then. You’ve generated a lot of interest in your post about Larimar. Keep asking questions and posting photos. What you have is seriously beautiful.
|
|
|
Post by rmf on Nov 22, 2021 18:10:00 GMT -5
With no machinery... yes it can be done. Why would you want to? I met a guy that polished Fluorite on his kitchen table finishing them with 1200grit sand paper for which he got an ok polish. Not sure Larimar would get as good but it would be an improvement. Start with 100/220/400/600/1200 but only use 100 if the saw left big marks. If not start with 220 because Larimar is soft. Ace Hardware where I live carries sheets of wet/dry 1200 grit blackish sandpaper. This guy just rubbed it no water on dry sandpaper while he watched TV. Yes his house was a mess but he was friendly. If you get to 1200 and need a better polish then you have to go to hardware or find 3000 grit sandpaper.
|
|
rewdownunder
spending too much on rocks
Member since March 2012
Posts: 357
|
Post by rewdownunder on Nov 22, 2021 18:15:05 GMT -5
Two ideas first try to find a rock club nearby that will help you. That is a great piece and you do not want to wreck it. Second search "hand polish" on this site and read everything you can. We have had this discussion several times over the last year and it always ends the same. Several of us have done it and will probable never try it again. It can take 100s of hours and you still have to buy all the grits and polish. Any rock club with a shop can teach you to do the job and have the equipment that members can use. With the right equipment that is about a 4 to 6 hour job to really do it right. I am slow others can probably do it faster. I wish you were closer I could just take you into our club shop and show you how to do it.
|
|
|
Post by Rockindad on Nov 22, 2021 18:49:51 GMT -5
Hamilton, ON Canada. I am about an hour from NY, Buffalo though I'll meet you at the border and take care of it for you-Peace Bridge, Lewiston-Queenston, Rainbow, you name it . Seriously though, higher grits of sandpaper are easy to find. Look for it under "automotive sandpaper". I think the highest grit I have used was 7000 or 10,000, extremely fine. Your local auto parts store may even have it, if not a minute or two online will get it for you. I've done this before and don't look forward to doing it again, but barring a major investment............ Don't know if it's any different by you but there is virtually no lapidary presence here- no clubs, shops, etc. and certainly a rarity to see any lapidary equipment come up for sale.
|
|
kouma
off to a rocking start
Member since November 2021
Posts: 15
|
Post by kouma on Nov 22, 2021 21:17:11 GMT -5
re: hand polishing Try a test run before you empty your supply of elbow grease. Beg, borrow or steal a teaspoonful of aluminum oxide polish and sprinkle some on a piece of denim. Dry. Rub one of the flat faces on the rag, vigorously, for about ten or twenty seconds and see what ya got. If you like what you see, then you can get some fine grits and do a better job on a piece of glass. Wet. Which grit you start with will depend on how true the cut faces are to begin with. Thanks parfive. I will buy some aluminum oxide polish and test it. I have other smaller pieces of Larimar so I will take before and after pics with the results. Regarding using grit on glass wet, is this grit sandpaper or powder form used in tumblers?
|
|
|
Post by jasoninsd on Nov 22, 2021 21:22:29 GMT -5
kouma - I just wanted to say welcome to the forum from South Dakota! You've really caused a stir (in a good way!) coming onto the forum showing a BEAST like this piece right out of the gate! I can't wait to see your final results with this piece - whichever way you choose to polish it!
|
|
kouma
off to a rocking start
Member since November 2021
Posts: 15
|
Post by kouma on Nov 22, 2021 21:32:05 GMT -5
kouma There is no manual that I know of. From your photos it looks like a pretty smooth surface. If there are big saw marks or breaks near the end of the cut, I would say weeks or even months of hand work to get it through 600 grit. The wet method is not difficult. Buy sandpaper that is made for wet sanding. Your local hardware store will have it. Keep it wet. I think pectolites are similar to asbestos, having a fibrous structure. You don’t want to breathe that into your lungs. Once sanded and polished they will be safe. If you don’t mind a curved surface on the cut faces, a good lapidary artist could probably help you. Another method would be to pour a decoupage epoxy over the surface. That will maintain the wet look but will be a pain if you want to do something different in the future. Incidentally, I have a big piece of Larimar somewhere. I rounded and polished one end. I don’t think it’s as nice as yours but I bought it in the Dominican Republic for 20 pesos. That was like $3 then. You’ve generated a lot of interest in your post about Larimar. Keep asking questions and posting photos. What you have is seriously beautiful. The surfaces are pretty smooth except for a small elevation (hill) at the top right corner of the left piece and top left corner of the right piece. I never imagined the process of polishing to be that time consuming, I am glad I asked before undertaking such an effort Using decoupage epoxy is an interesting approach. I might test it out on one of my smaller rough pieces and see the results. Thanks for the suggestion and I will definitely share more photos as I proceed.
|
|
kouma
off to a rocking start
Member since November 2021
Posts: 15
|
Post by kouma on Nov 22, 2021 21:44:03 GMT -5
Two ideas first try to find a rock club nearby that will help you. That is a great piece and you do not want to wreck it. Second search "hand polish" on this site and read everything you can. We have had this discussion several times over the last year and it always ends the same. Several of us have done it and will probable never try it again. It can take 100s of hours and you still have to buy all the grits and polish. Any rock club with a shop can teach you to do the job and have the equipment that members can use. With the right equipment that is about a 4 to 6 hour job to really do it right. I am slow others can probably do it faster. I wish you were closer I could just take you into our club shop and show you how to do it. Thank you rewdownunder! that is a great suggestion. I am sure there must be a club like that in my area and if they are half of how friendly you and the others are on this forum, I am set! Funny I came here thinking this might be a few hours effort... polishing is no joke it seems
|
|