"shattered" pieces of gold or silver? (maybe question for Peter)

I'm trying to come up with a technique for making small bits of gold
or silver with the appearance of weathered stone blocks, broken stone,
etc., but on a jewelry-sized scale. Which "bits" would then be
granulated onto a backing piece. We are talking small enough "bits"
that casting them from wax patterns (leaving aside how the waxes
themselves might be made...) seems impractical.

I ran across a thread where Peter discusses some experiments he did in
grad school with quenching from an elevated temperature to crack or
fracture the metals in interesting ways. So, Peter, did you ever get
anything like what I am looking for? Any tips?

Also, does anyone know if it is possible to shatter gold or silver by
ultra-low temperature cooling, followed by impact? Like, for
instance, chilling a piece in liquid N2 and then dropping or
projecting it against a hard surface, or striking it with a hammer?
So far, I haven't been able to find anything definitive about whether
precious metals undergo such a phase transition between malleable and
brittle states at low temps.

TIA for any help.

Regards,

Bob

On Sun, 12 Sep 2004 13:11:26 -0700, in |õ (Bob
Edwards) wrote:

I'm trying to come up with a technique for making small bits of gold
or silver with the appearance of weathered stone blocks, broken stone,
etc., but on a jewelry-sized scale. Which "bits" would then be
granulated onto a backing piece. We are talking small enough "bits"
that casting them from wax patterns (leaving aside how the waxes
themselves might be made...) seems impractical.

I ran across a thread where Peter discusses some experiments he did in
grad school with quenching from an elevated temperature to crack or
fracture the metals in interesting ways. So, Peter, did you ever get
anything like what I am looking for? Any tips?

Also, does anyone know if it is possible to shatter gold or silver by
ultra-low temperature cooling, followed by impact? Like, for
instance, chilling a piece in liquid N2 and then dropping or
projecting it against a hard surface, or striking it with a hammer?
So far, I haven't been able to find anything definitive about whether
precious metals undergo such a phase transition between malleable and
brittle states at low temps.

TIA for any help.

Regards,

Bob

What I was doing was quenching previously formed shapes made in about 20 or 22
guage sterling silver. quenching from too hot a temp would crack the metal in
ways that looked more shattered and cracked than I could have done with a
sawblade. but it didn't actually break apart into multiple pieces. Note too,
that the sheet metal was stock I'd made myself, from ingots poured and then
rolled with intentional underannealing, as well as probable flaws in the ingot,
in hopes of accentuating the flaws that would show up in the final sheet. Worked
just fine.

For your use, it seems to me that any sort of cold attempts to shatter the metal
won't look right, what with the remaining ductility of the metal leading to
bright shiney tool marks and the like. what you might try doing is heating it
without flux, a slightly oxidizing flame, so it the surface gets kinda crumbly
looking with oxidation, and, at just barely below the temp at which it would
actually melt and bead up, break up the metal with something like a carbide
poker. At elevated temps, it's got little strength, and if you can control it
right, you might be able to just break it up with the crystal shapes still
showing a bit, with oxidation and fire scale accentuating the effect. After
pickling, it might be near what you wish. Worth trying, at any rate.

another thought might be something like just using nippers, perhaps with bad
jagged edges, to chew small bits of metal off a previously roughed up bit of
sheet metal or other stock. Not cutting all the way through, but taking small
nips such that each bit of nip doesn't meet the previous ones quite right will
give you rather chewed up bits of metal. Then tumble these with a really coarse
abrasive to knock down the sharp and bright edges. something like that, if you
get the sequence of tumbling media right, might give you a look you like...

Good luck

Peter

Perhaps make some shapes out of precious metal clay (PMC), then break
'em prior to burn-out? Just a thought.

Cheers!
Neil

Bob Edwards wrote:

I'm trying to come up with a technique for making small bits of gold
or silver with the appearance of weathered stone blocks, broken stone,
etc., but on a jewelry-sized scale. Which "bits" would then be
granulated onto a backing piece. We are talking small enough "bits"
that casting them from wax patterns (leaving aside how the waxes
themselves might be made...) seems impractical.

A couple of thoughts, try casting onto a layer of broken glass, auto
'safety' glass from a body shop, and try busting up a bottle or window
pane. Even casting into a pile or can of glass sahrds and then picking
out some fun pieces or manipulating further with semi-flush cutters as
Peter suggested. Maybe pouring some sterling onto a piece of drusy
quartz could work for you. I'm also wondering if a reticulation alloy
instead of sterling may be a good choice for your project, with the
above techniques or some suggested by others. Reactive Metals sells it,
or you could alloy your own.
sounds like fun - try to let us know what you end up with OK?

Carl
1 Lucky Texan


Bob Edwards wrote:
I'm trying to come up with a technique for making small bits of gold
or silver with the appearance of weathered stone blocks, broken stone,
etc., but on a jewelry-sized scale. Which "bits" would then be
granulated onto a backing piece. We are talking small enough "bits"
that casting them from wax patterns (leaving aside how the waxes
themselves might be made...) seems impractical.

I ran across a thread where Peter discusses some experiments he did in
grad school with quenching from an elevated temperature to crack or
fracture the metals in interesting ways. So, Peter, did you ever get
anything like what I am looking for? Any tips?

Also, does anyone know if it is possible to shatter gold or silver by
ultra-low temperature cooling, followed by impact? Like, for
instance, chilling a piece in liquid N2 and then dropping or
projecting it against a hard surface, or striking it with a hammer?
So far, I haven't been able to find anything definitive about whether
precious metals undergo such a phase transition between malleable and
brittle states at low temps.

TIA for any help.

Regards,

Bob


--
to reply, change ( .not) to ( .net)

Bob Edwards wrote:

I'm trying to come up with a technique for making small bits of gold
or silver with the appearance of weathered stone blocks, broken stone,
etc., but on a jewelry-sized scale. Which "bits" would then be
granulated onto a backing piece.

You could try texturing a (thickish) sheet with various tools;
then cut it into chips. If you find the right
tool for your flex shaft you can apply texture to the edges of
each chip quickly.

I don't really think any heat treatment is going to make that
weathered look.
--
mbstevens
http://www.mbstevens.com

Bob Edwards wrote:

I'm trying to come up with a technique for making small bits of gold
or silver with the appearance of weathered stone blocks, broken stone,
etc., but on a jewelry-sized scale.

Melt small amounts of gold on a charcoal block. When the gold is molten and has
formed into a ball, hit it with a hammer with a large flat surface. A medium
sized chasing hammer is perfect for this. Do not hit the gold ball too hard,
because then the resulting piece will be too thin. You'll figure it out.
Afgter several tries you may end up with a few pieces you'll like.

One very important thing to remember. Do all of this INSIDE a circular metal
barier, and on top of a metal sheet, so that the hot gold does not go flyinbg
everywhere, and or hits you in the chest.

Good luck.

Abrasha
http://www.abrasha.com

"Abrasha" wrote in message
...
Bob Edwards wrote:

I'm trying to come up with a technique for making small bits of gold
or silver with the appearance of weathered stone blocks, broken stone,
etc., but on a jewelry-sized scale.

Melt small amounts of gold on a charcoal block. When the gold is molten
and has
formed into a ball, hit it with a hammer with a large flat surface. A
medium
sized chasing hammer is perfect for this. Do not hit the gold ball too
hard,
because then the resulting piece will be too thin. You'll figure it out.
Afgter several tries you may end up with a few pieces you'll like.

One very important thing to remember. Do all of this INSIDE a circular
metal
barier, and on top of a metal sheet, so that the hot gold does not go
flyinbg
everywhere, and or hits you in the chest.

Good luck.


HeH. I had 14.5 gm of 18K melted on top of a brand new charcoal soldering
block that I had groved for a wire mold. Did you know that molten Gold
rolls toward the flame? Did you know that molten Gold continues to roll
after you remove the flame? I ended up with 14.5 gm of Gold shot ranging
from 1/2 mm to 2 mm in diameter slightly flattened on the bottom. Now I am
thinking of using that shot with some "Gold Glue" ( Malachite + Gum Arabic +
Boric Acid + Sodium Borate + Alcohol ) to granulate a ladies bracelet with a
nice Opal as the stone. I used an old cast-Iron dutch oven to catch any
spills but I had intended to roll that particular melt into wire. I did get
my wire made by wiring a second charcoal block on top with the original as a
"mold" and tilting the melt into the channel. Learn something new every day
I guess.

--

Don Thompson

~~~~~~~~


Abrasha
http://www.abrasha.com

"Don T" wrote in message
. ..

HeH. I had 14.5 gm of 18K melted on top of a brand new charcoal soldering
block that I had groved for a wire mold. Did you know that molten Gold
rolls toward the flame? Did you know that molten Gold continues to roll
after you remove the flame? I ended up with 14.5 gm of Gold shot ranging
from 1/2 mm to 2 mm in diameter slightly flattened on the bottom. Now I am
thinking of using that shot with some "Gold Glue" ( Malachite + Gum Arabic +
Boric Acid + Sodium Borate + Alcohol ) to granulate a ladies bracelet with a
nice Opal as the stone. I used an old cast-Iron dutch oven to catch any
spills but I had intended to roll that particular melt into wire. I did get
my wire made by wiring a second charcoal block on top with the original as a
"mold" and tilting the melt into the channel. Learn something new every day
I guess.

--

Don Thompson

Don:

Been there, done that! :-)

BTW, you don't need such an elaborate formula for granulating -- just
mix up some hide glue and green flux with a bit of water. I'm away
from my shop now, and doing this from memory (so don't hold me to it),
but I think the ratios are 50 drops water, 10 drops green flux, 5
drops hide glue. I use Titebond, works fine. The ratio isn't really
that critical, you can adjust it to your preference. It helps to
copper-plate the granules first, by stirring them in some well-used
pickle with an iron tool, but again, it's not strictly necessary, just
makes the process a tad easier, espcially with 18kt.

The glue provides the reducing atmosphere and sticks the granules
down, the copper plating helps with the micro-alloying at point of
contact, and the flux helps keep everything from oxidizing.

The plating disappears when you fuse the piece. Also, you should
depletion-gild the base piece by repeated heating and picking until no
oxide forms on heating.

Regards,

Bob

Some good suggestions that I hadn't considered -- thanks guys!

I'll let you know how this turns out.

Regards,

Bob