How long does it take to cut a sapphire?

[athenaworth]

I'm getting so excited! I got an email from Jeff White that he was cutting my potential sapphire last night, and now I'm biting at the bit. It'll be approximately 6.5-7mm. How long does that usually take?? Guesstimates are fun.

 

[bright ice]

Not sure but it's a processs from what I gather. He started on my spinel well over a week ago on the process of rounding he called it. I talked to him yesterday and he is going to have it finished by the end of week. He sent a blueprint of my cut design. It's going to be a beautiful pattern.

Can't wait to see what you get.

 

[ooo~Shiney!]

Oh, I can't wait to see what you BOTH get !!!!!!!

 

[PrecisionGem]

The average stone takes anywhere from 1.5 hours to maybe 6 hours if it's large, and a complicated design and there are issues with it. Normally nice blue sapphires that any of the cutters are cutting are re-cuts of commercially cut stones. Some countries won't allow rough stones out of the country, as they want to created jobs at home, so the only way to get a stone is to buy a cut stone and recut it. There's no need to spend time deciding on how to orientate a recut, so the process could be less time.

 

[MontageCreations]

Gene's assessment is correct, but that doesn't mean we can turn a cutting order around in a day or less, well maybe he can . I am usually 'cutting' about 30 stones at a time, all of them are in various stages of the process, so although I may only have 2 hours total cutting time in a stone, I am not working on it continuously for 2 hours, I spend 10 minutes on it, then do another one in the same stage of the process, then another, etc. till I have 8-10 ready for the next stage, etc. We do this because there is downtime between stages, changing laps, cleaning, etc. So even though it may take just a few hours to cut your stone, it can take a week or more to go through the process.

Many years ago for a special order, I spent more than 200 hours on a single stone. I have a LARGE white topaz (680 carats), that I have been cutting here and there for about 2 years, more than 300 hours and not half done.

 

[mastercutgems]

I agree with Gene as it all depends on the stones size and complication of cut... Yes these days unless you are working with African or Montana sapphires the re-cut is normally the deal; same way with the Burma spinels.

I normally do not take a gem out of the machine until the pavilion or crown is complete; then I do the transfer dopping to change from pavilion to crown. It just leads to less cheating if I complete one end and then the other. Now it may be 3 days before I get around to cutting the crown but like MC I too may have 12 plus stones in the dops in different stages; but I have only 2 stages, totally uncut, and pavilion cut and polished and ready for cutting the crown and table... Simple minds simple pleasures If it gets too complicated I may mess up something

As for sapphires I have cut some with no issues that may have taken total time of 2 hours; say a 7mm zircon culet standard round brilliant; and I have cut some that had rutile needles and they gave me a fit in polishing that took 5 hours; also tables can give you a fit. The bigger they are the worse it is; I know I used to cut huge gems in the 300 carat range; but the last one took me 4 hours to polish the table; so I do not do those any longer; let someone younger and with more free time take on those monsters

Good question as it really all depends on many things; some in our control and some out of our control... I know sometimes we get burnt out on a mineral and we just need to change minerals to save sanity

Most respectfully;

Dana

 

[PrecisionGem]

Gene's assessment is correct, but that doesn't mean we can turn a cutting order around in a day or less, well maybe he can . I am usually 'cutting' about 30 stones at a time, all of them are in various stages of the process, so although I may only have 2 hours total cutting time in a stone, I am not working on it continuously for 2 hours, I spend 10 minutes on it, then do another one in the same stage of the process, then another, etc. till I have 8-10 ready for the next stage, etc. We do this because there is downtime between stages, changing laps, cleaning, etc. So even though it may take just a few hours to cut your stone, it can take a week or more to go through the process.

Montage, that sounds like a rather inefficient way to cut, unless you are maybe cutting 8 stones all identical size and design. I'd think you would spend more time removing the stone from the machine, putting in the next stone and lining it up, than simply changing a lap. But even then you would need to work your way down until you found the smallest stone. Doesn't seem like good yield. Of course if you are cutting topaz or quartz who cares about yield. I'll normally do 2 pavilions in the evening after dinner, and then transfer them, then the next night do the two crowns. 90% of the time they are different material and designs.

A lot of the time depends on the design, and any problems you work into in the stone. Rounds are the fastest cut. The more symmetry to a stone the faster it is to cut. It also has a lot to do with the material. Typically spinel and tsavorite are weird shapes in the rough, and the rough is expensive, so you can spend a lot of time deciding on the approach to the stone, and then once you get into it, may have to change things up to save some weight.

 

[MontageCreations]

Montage, that sounds like a rather inefficient way to cut, unless you are maybe cutting 8 stones all identical size and design. I'd think you would spend more time removing the stone from the machine, putting in the next stone and lining it up, than simply changing a lap. But even then you would need to work your way down until you found the smallest stone. Doesn't seem like good yield. Of course if you are cutting topaz or quartz who cares about yield. I'll normally do 2 pavilions in the evening after dinner, and then transfer them, then the next night do the two crowns. 90% of the time they are different material and designs.

A lot of the time depends on the design, and any problems you work into in the stone. Rounds are the fastest cut. The more symmetry to a stone the faster it is to cut. It also has a lot to do with the material. Typically spinel and tsavorite are weird shapes in the rough, and the rough is expensive, so you can spend a lot of time deciding on the approach to the stone, and then once you get into it, may have to change things up to save some weight.

I don't use a mast machine, a lot of the time lost in resetting the mast, alignment of the dop, re-indexing, cheating from one cut to another is not a factor. So for me the time I lose is in changing the lap, cleanup of the splash pan, etc. Different strokes for different folks. It's more efficient for me to change stones and keep cutting.

 

[ruffysdad]

In a straight timeline Gene's about right although in my case the real world keeps intruding on my cutting time. Useless things like my job (gotta keep packing that 401k), honey-do's and important things like Ruffy (he likes stimulating conversation with his meals so I've got to go keep him company in the garage at mealtime ). For me, working around this stuff usually means 2-5 days/stone to turn out a finished one.

Pete