Lapidary/Polished Stones

[Plays In The Dirt]

Very cool amigo - now for a dumb question.

How did they polish stone in ancient times? Thank you in advance,
Roy

The following link explains how they formed artifacts in ancient times. Not quite polishing but reading it shows that they used sand and water to do so.

http://www.uiowa.edu/~osa/learn/ancient ... stone.html

The Chinese used diamonds to polish stone.

http://www.sciencedaily.com/releases/20 ... 135123.htm

[roc2rol]

excellent links above

Then I was able to get the rest even on the faceting machine, then I worked on the faceting the heart shaped "chunk". (I did do some polishing on the edges after I did the faceting - which was also quite an ordeal).

I completely understand! We have to work with resources we have at the time. I've contemplated how one would form a heart shape on a flat lap. No good answers till you came along!

That’s the challenge and the hard fought creativity of the process.

The preferred method is to use a template and draw out the heart pattern on the stone. Then rough cut out the heart pattern on the saw. For shaping the heart, using the periphery of a grinding wheel is probably the best method. With the corner of silicon carbide wheel you can hold the stone at the desired angle to grind out the cleavage or m-part. All free hand & fun-- watching the heart form take shape!

[Mrs.Oroblanco]

Roc2rol,

I actually considered the template idea - unfortunately, it wasn't until I had already worked on the first (and only) heart.

I think your way of doing it, might be considerably better than the way I tried it. (nothing in my books really explained how to do roundish things, other than cabachons,) and of course, they aren't usually faceted. My biggest worry was having enough material left to facet (and make mistakes with, that had to be refaceted). Does that explanation make sense, the way I said it? Every time you have to refacet, you lose material, and you have to "catch up" on that material loss on the opposite side. (and hope you don't make a mistake there), so the piece gets thinner and thinner.

I would really like to find a better way. Maybe the half/half and epoxy would work. Is the epoxy you use the same epoxy used to mount a stone on a flat bezel? (and comes out clear)?

Beth (Mrs. O)

[roc2rol]

Hi Beth,
I’d love to see a roc’n heart faceted!

But I’m not sure if that’s the best course of action at this stage of the game.

I know you don’t have a faceting machine now
but if you got one I would think the best thing to do,
would be to make a pre-form heart out of single rock
& do more experimenting
Is there a lapidary shop/classes around your area?
you could use there equipment

Let me ask a question about the faceting of a heart.
Do you grind a table on it?
Where do you start the first angles at?
The m-part or the bottom point?
Or does it matter ?

My biggest worry was having enough material left to facet (and make mistakes with, that had to be refaceted).

sure it makes sense to me -but I know how difficult it is to state things technically
heck I have trouble putting two plus two together
anyways… its amazing how fast a stone can disappear in a finishing process
but rough grinding is a long laborious process!

Ed

[oroblanco]

Roc2rol wrote

its amazing how fast a stone can disappear

So, you heard about my one-and-only attempt at tumbling stones to try to polish them huh?

I left them in the tumbler for a couple of weeks, and when I checked on them - the stones were gone! Only sand left! First lesson in rock polishing, the importance of hardness!
Roy

[roc2rol]

Roc2rol wrote
! Only sand left! First lesson in rock polishing, the importance of hardness!
Roy

ah yes Roy !
but what fine polished sand granules they be!!

[Mrs.Oroblanco]

roc2rol,

Honestly, I don't know what the correct way is - I was going by guess and by golly!

I kind of did an egg-shaped kind of thing first, to get all the sharper edges off it (like a real fat cabachon). Then I took a marker pen and a little ruler to try and find the very middle. I started at the bottom (the V) - my hope being that, since there is less faceting there, that I could use that for the next row, which of course, had more. Boy, it is hard to explain, especially when, like I said, I was going by guess and by golly. I did make up some popsicle sticks (don't laugh), that had the angle on them (I cut the sticks to match the first set of facets I did and numbered them), and tried to match them up with the next set - and when I got to the other side of the heart-hoping to match them. They don't match exactly, but it helped. If I had been smarter at the time, I think I would have actually made an angle IN the stick instead of using just an angle at the end of the stick. (like a gauge).

This is assuming I would ever try that one again

I'm looking around now for another faceter. My "room" is almost ready for occupancy, so, I'd like to find a decent one in the next couple of months. (I just want it to match the lap sizes I have left). I still have rocks left to screw up!

Beth (Mrs.O)

[roc2rol]

Mrs O

I know you had ground the bottom flat.
How thick was the rock?
Was the top flat also
or
was it somewhat dome shape?

if dome shape did you do that on the flat lap?

heart of saturday night

[Mrs.Oroblanco]

Yea! That's the way it started!!! (that's the way I started). It was an uneven chunk, with same flaws and cracks, etc., in it. Tried to pick the best part out first (of course), rounded it like the egg-shape, and flattened the back - and then did like your picture, when I got to faceting time.

I like that picture! Is that in one piece? If so, how was the M part of the heart done? (same questions you asked, isn't it?)

Beth (Mrs. O)

[roc2rol]

No that a two part heart
with a little added photoshop

I did do some hearts from a single stone
but never really used a template
onery
I like to do them free hand
here’s one I call heartbreak hotel


that quartz vein is translucent when backlit

I was wondering if you had any pics of your wood mosaics?
I know we can't veer off on to that
but I’m really interested
in all things mosaic, intarsia, marquetry ect….

Big hello to all of ya from Phoenix !
Ed