Technical Advice for Cutting Stones

Though I would start a new thread and ask a question that has prevented me from dropping a small yellow sapphire for fear of stuffing it up. The photo shows the cut and rough shape of the stone, so you can see why I chose this diagram.

What is missing from the instructions I have is where to centre the dop needs to be situated on the long axis. I have marked where I am taking a wild guess but thinking the cuts will not produce the level girdle shown on the diagram as all faces are not symetrical around a single axis. Anyone had experience with one of these they would like to share?

Haven't cut one of those before Wally - is that one of Vargus's designs?

Where you've got it looks logical to me since the culet is going to end up under the dead centre of the dop.

You would be hard pressed to find someone with more faceting experience than Tony, if you still have a few doubts before trying it on a sapphire it might be a good idea to ask him.

Cheers Lefty, just looked at the stone a bit closer and the darn thing was concealing a veil right down the guts of it. :argh:

Slapped it on the dop anyway and thought I would share a before shot as it may be the only photo I bother taking.......and it just happened to shine the way it was in my dreams last night......didnt even need to cut it. :inlove:

Oppps, forgot to answer your question, yes, it is out of Volume 3. Would like to get my hands on volume 1 and 2 to see what is in them.

Here is a clearer shot, the clear yellow is breathtaking (and never adequately represented in the photo) but the stone is too small for me to cut the veil out. It also has some reds and oranges on a few of the cleavages, might try to leave some in. And have a play and see what happens.

Bummer dude - don't ya hate that when it happens? :awful: shame, nice colour there, yellows are probably my favourite.

I've got volume 2 of Vargus's"Diagrams for faceting" here. A lot of interesting stuff here from when before meetpoint became a thing. I haven't cut many of the designs in it as they are written in a very old school format which sometimes makes them a bit difficult to follow. Some intersting stuff in it though.

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Thought I saw the info on dopping positions for a pear somewhere, had a look around our books and it's in John Broadfoot's book, page 199. In his words; "The dop has to be centred at a point that is half the width or the design from the rounded end of the proposed pear shape" I have also seen comments about working a 1/3 - 2/3 ratio for dopping, but I think I'd use Johns guide for my preference.

Seem to remember I used the 1/3rds rule when I dopped this citrine, but looking at the result the culet seems to follow the W/2 rule rather well.


Oops, probably should have cleaned it first :8 Stone finished at 1.6ct so quite small.

Nice one there Dihusky :Y: What's the design called?

Thanks Lefty, it's Akhavan's 'Ideal'

Ah, and Akhavan one - I'll have to look it up now.

The bloke was certainly a prolific and imaginative faceting designer in his spare time (he's a surgeon, cuts people for a living and rocks for a hobby ) Spoke to him a few times on GO, he actually wrote a design for me (which I don;t think I ever got round to cutting :8 )

As well as an imaginative designer, he's an imaginative design namer, with faceting diagrams called things like "Vincalis the Alligator" and "To Zanzibar by motor car"

Thanks Hu,

Having had a bit of a play with it last night, thinking that stone design can only be done around the axis of the dop, to replicate a design cut on fixed angles you must start with enough rough size to support the fixed-angle design.

The Vargas design I chose enables the lengthening of the stone by extending the middle facets and this has the effect of changing the relativity of the the dop centre, indicating centring around the non-variable facets would speed up the cutting.

Thanks for sharing you photo, looks great. I have avoided cutting pears, kites and other elongated shapes to date, but the more I look at them, the more I like them

A good read this. Thanks all
Mackka

Far too complicated for me. I will leave it to the experts.

pete165 said:

Far too complicated for me. I will leave it to the experts.

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It's not that difficult to learn the basics pete - the main thing you have to have is patience

Lefty said:

pete165 said:

Far too complicated for me. I will leave it to the experts.

Click to expand...

It's not that difficult to learn the basics pete - the main thing you have to have is patience

Click to expand...

And an eye for detail :awful:

Yes, that always helps as well

I would dop exactly where you circled (maybe a touch down towards the back a bit. Start with the girdle cuts to get your shape, then every thing falls into place. The trick with dopping like that is the short girdle facets on the point are an eyeball job, but it gives you a bit of freedom to make them as long or as short as you want.

Considering this design is not a complicated one and is mostly a stepped cut, the facets should line up where ever you put them.

I would use facet G1 (assuming by extention facet 1 on the crown) as your facet setting point. Simply line up all facets one by one to that grouping. (G1, P1, C1)

If that make sense at all.