Fraud with Gold of 18K

[justinhcase]

thank you I will amend my diction to the local norm.
but not to labor the point.if you read the story at the time there was the alloy that was created the tungsten ring that had been left and considerable amount of flux in the crucible at the time.
This being multiple entities combined into one form I thought that it would be acceptable to use the abbreviated word for amalgamated to describe it.I am aware that in dentistry the term amalgam implies exclusively to a mercury alloy but in business and the military it can be used to describe the coming to gether of different components.and in engineering we would never use such a loos term with out specifically calling it a mercury amalgamation.
So very sorry for the guff please forgive me.

 

[Harold_V]

This being multiple entities combined into one form I thought that it would be acceptable to use the abbreviated word for amalgamated to describe it.

In a metallurgical sense, no, it isn't appropriate, as in that field, amalgamation is the combining of metallic elements with mercury (such as silver, tin and copper to form dental amalgam). To misuse the term is to imply that mercury is a part of the total, and it clearly is not. As I said, what you are describing can be considered an alloy, or even a solution. Unless mercury is involved, it is NOT an amalgam.

If I am mistaken, please point me to the proper source of information.

Harold

 

[butcher]

I probably have used the word amalgam in a sentence where it should not have been used, and I should have used the term alloy.

Amalgam

Amalgam from the Greek words for together, to join.

An alloy of mercury with another metal that is solid or liquid at room temperature according to the proportion of mercury present .

A mixture of different elements.

Synonym a mixture
a mixture or combination: {His character is a strange amalgam of contradictory traits}.

When the word is used to describe metal alloys, it does look like mercury is involved in the alloy.
where mixture of metals alloys can occur by contact with mercury normally without heat, where the mercury acts as a solvent in contact with other metals, mercury being a liquid metal at room temperature.

Amalgams seem to involve mercury (I could not find any alloys described as amalgam that did not), mercury amalgams with many metals without heat in order of ease, gold, silver, lead and tin, mercury will amalgam with most all metals, In fact every known metallic element, excepting only platinum and iron, dissolves in mercury, at one time, mercury was stored in iron bottles. but is difficult to mix copper, it will mix with copper when heated to a high heat, or if mercury is in an oxidized state.

Even the alkaline earth metals, such as calcium, strontium, and barium can form compounds in the amalgamation process. Also, ammonia forms a very reactive amalgam.

An amalgam is more than a solution. A solution is comprised of one or more substances dissolved in one or more other substances called the solvent.

some examples, silver amalgam used in dental work, tin and mercury used for mirrors, gold or silver amalgams in mining recovery of metals, most all of these processes are outdated, and new safer and better processes have replaced or are replacing the amalgam processes.

The Difference Between an Alloy and an Amalgam -
by Professor Xu Wang of the University of Akron
An interesting read on this subject:
http://www.its.org/node/5666

I will try to use the words or terms amalgam, and alloy where they should be used, now that I understand them a little better, thanks.

 

[kurtak]

But getting back to the original query do you think any of the electronic test set's that say they can detect deep filled items actually work or will we have to keep hacking thing's in half

Not that I am aware of - the acid/electronic test set's will only tell you the exposed surface it is testing so even if you scratch the item being tested it will only tell you the new exposed surface

An XRF will read a bit under true surface but only enough so that it will tell you it suspects "possible" plating & in order for an XRF to tell you that you need to let it read the item for a couple minutes

Kurt

 

[justinhcase]

The Amalgamated Transit Union is a labor organization in the United States and Canada that represents employees in the transit industry. Established in 1892 as the Amalgamated Association of Street Railway Employees of America, the union was centered primarily in the Eastern United States; today, ATU has over 190,000 members throughout the United States and Canada.

Amalgamation is a now largely archaic term for the intermarriage and interbreeding of different ethnicity or races. In the English-speaking world, the term was in use into the twentieth century. In the United States, it was partly replaced after 1863 by the term miscegenation. While the term amalgamation could refer to the interbreeding of different white as well as non-white ethnicity, the term miscegenation referred specifically to the interbreeding of whites and non-whites, especially African Americans.
The term amalgamation was derived from metallurgy (see amalgam). It has been linked to the metaphor of the melting pot, which also originated in the US, and which described the cultural assimilation and intermarriage of different ethnicity. The intermarriage of whites with African Americans and, to a lesser degree, other non-whites was until recently in social disfavor in the United States, despite the long history of informal liaisons between white men and nonwhite women during the long years of slavery and after emancipation. Until 1967, interracial marriages were prohibited in many US states through anti-miscegenation laws.

A merger, consolidation or amalgamation, in a political or administrative sense, is the combination of two or more political or administrative entities, such as municipalities (in other words cities, towns, etc.), counties, districts, etc., into a single entity. This term is used when the process occurs within a sovereign entity.


the amalgamation of church and state
The principle of separation of church and state is documented in the first amendment to your constitution. Its importance derives from the historical fact that state sponsored religions have been a primary source of tyranny in numerous countries and societies. your founding fathers wanted to avoid any possible occurrence of an alliance of religion and civil government there, and thus the constitution strictly prohibits the establishment of a favored religion in your society.

But as I say sorry for using a term for its meaning out side that set out by Hook.
By the way is she the only female contributor??pity as her methods give me the horn

 

[niteliteone]

From what I understand;
An "Amalgamation" has many uses in language and basically means "combining stuff"
An "Amalgam" is specifically a mercury + ___ metal combination when dealing with metals.

On this forum specific and proper usage of vocabulary is mandatory to avoid mistakes or worse.
The word was used improperly from the beginning and no amount of ___ can excuse that.

Lets get back on topic 8)

 

[justinhcase]

Just seen again Amalgamite the award winning invention!
I knew I had seen the dreded word used in a syntax before not to do with Hg.

 

[kurtak]

It doesn't matter how its used elsewhere ---- here it means mercury is in the mix

Kurt

 

[Geo]

Just seen again Amalgamite the award winning invention!
I knew I had seen the dreded word used in a syntax before not to do with Hg.

This issue has been put to rest. To persist might risk you seeming to be disruptive. The forum should be considered a class room and should be treated like one. We all come here to learn and we learn from the people that know and already have the experience. The coarse of action is clear, when you are talking to your friends and acquaintances about refining, you can describe it as you please. While you are here, please use the accepted terms from the forum. It helps to alleviate confusion of having multiple names for a single object or concept.

 

[justinhcase]

sorry to cause offense .
I was enjoying a good debate with what I thought where people similarly engaged.
My last query was why they have named the lattes supposedly miracle method of gold extraction after a substance it douse not contain?
I always want to understand better and have a compulsion to ask why.
I beg your indulgence if I appear to have acted in ignorance.
and P.S. no offense but "because I told you so" has never been a valid scientific explanation to me.

 

[cmiller92]

I have seen a very similar thread where someone always needed to get the last word in, needless to say but I will anyway...they were banned. It might be wise to retract the last statement in your apology, our very respected and senior member, Geo, might take offense.

 

[Geo]

No offense taken on my part. I apologize for sounding like i was chastising as thats not my intention. I am not a moderator and don't pretend to be one. I am simply stating the facts and trying to give some direction. I would hate to see someone make a simple mistake and then add insult to injury by not taking the suggestions to let something go before it escalates. If anyone thinks that i have overstepped my boundaries, they should let me know and I'll try to modify my behavior to better suit them.

 

[butcher]

I actually found this amalgamation of thoughts, and ideas from all of the members, and this discussion about the metal amalgam (with mercury), as opposed to alloys very interesting, and educational.

Although an amalgam of metal is a mixture of metals which includes mercury in the alloy, an alloy or mixture of metals without mercury just is not called an amalgam of metals, but is considered an alloy of metals.

Mercury is not the only metal that is liquid, and will dissolve metals at a low temperature by contact, gallium a metal that will melt in your hand, gallium will also attack most other metals by diffusion into their metal lattice, making a mixture of metals (an alloy, but. Here I suppose like mercury it would not be considered a true alloy, as the mix is probably not a solution "Per Se", but would be similar to how mercury and other metals form the mix of metals in the mercury amalgam).

I am not sure I understand all of this correctly but it is all just fascinating to me.

Many metals will migrate or form a mixture where they contact, at the grain boundary where a thin portion of the metals may transfer or share electrons, even other instances where metals or dissimilar metals in contact can act as battery's with galvanic action,oxidation and reduction can also occur on contact (with moisture and air, gases and liquids acting as electrolytes in some cases) (over time or faster under high heating) many factors, of the circumstance which results in a chemical reaction of metals in contact with each other ...

I am unsure if moisture or some form of electrolyte would even need to be involved, or just close contact through bonding is all that is needed, which seems to be the case in some instances).

Heating metals to high temperature where one of the metals melt, the lower melting metal will also dissolve the higher melting temperature metal it is in contact with, (like tin will dissolve gold at the melting point or soldering point of tin), this molten metal (tin in this example) lowers the melting point of gold where they contact, or when melting metals to form alloys we can the form mixture of metal and at a lower melting point of the metals involved in the mix, the metal with a lower melting will become the solvent for the other metal, and will melt (the higher melting point of metal in the mix, well below that of the metal with the higher melting point, gold here will melt at a lower temperature than the pure metal itself would melt. the alloy having a lower melting point than the metals involved in the alloy would on their own...

I do like this discussion and like learning where I should use the proper terms and why. With the why which is what I really like to know, sometime leads to me learning more about how these metals react with each other, and things around them.

Language (not only English) is a funny thing sometimes, I used to think it did not matter how or what you said, the whole point of communication was to understand each other.

When we all use the same term or meaning for an alloy or amalgam we will all understand each other better, and what we are discussing, improving our ability to communicate our meanings with each other, so my thoughts on language have changed somewhat, using the right word in the right place can help us to communicate and understand each other better.

Being on a forum where we talk with a keyboard, and cannot see each other (making it even harder to get ideas across), communication of thoughts and ideas is harder, here words typed, and read are what we have to go by, making communication a bit more challenging, (misunderstanding each other easy), so if we all type the same word having the same meaning in mind we as readers do not misunderstand each other as much...

And Knowing why and learning more is the fun part of this science of metals.

 

[g_axelsson]

Heating metals to high temperature where one of the metals melt, the lower melting metal will also dissolve the higher melting temperature metal it is in contact with, (like tin will dissolve gold at the melting point or soldering point of tin), this molten metal (tin in this example) lowers the melting point of gold where they contact, or when melting metals to form alloys we can the form mixture of metal and at a lower melting point of the metals involved in the mix, the metal with a lower melting will become the solvent for the other metal, and will melt (the higher melting point of metal in the mix, well below that of the metal with the higher melting point, gold here will melt at a lower temperature than the pure metal itself would melt. the alloy having a lower melting point than the metals involved in the alloy would on their own...

I do like this discussion and like learning where I should use the proper terms and why. With the why which is what I really like to know, sometime leads to me learning more about how these metals react with each other, and things around them.

Prepare to learn some more then... anyone not interested in learning some physics better stop reading here. :mrgreen:

In the first part you used the correct terminology, solvent. But then you started to talk about "tin is melting gold". That's wrong! Tin is dissolving gold at below the melting point of gold. Just as we dissolve metals in acid or sugar in water.
Melting is a quite well defined physical process and classified as a "first-order phase change" while dissolving something is a "second-order phase change".

Okay, I could go quite a lot deeper into theory but that would only scare away the few brave souls that read so far... The easiest way to look at it is to see what happens when you heat a closed system.

Melting : Take a block of ice from the fridge and place it in a pan on the stove. When heating it (slowly) the temperature will rise until it reaches the melting point of ice. There the temperature will be fixed until all ice is turned into water. Then the temperature will continue to rise.

Dissolving : Take a glass of water and add a hefty dose of salt so it becomes saturated. Now if you heat it more salt will dissolve while the temperature is rising. In this case the temperature is changing while the phase change (solid -> dissolved) is taking place.

So, first-order phase change then the temperature is fixed during the change, while second-order phase change changes temperature during the phase change.

So the correct term to use is "tin will dissolve the higher temperature melting gold" and if you saturate the tin with gold you can add heat and raise the temperature to dissolve even more gold.
"Gold here will dissolve at a lower temperature than the pure metal itself would melt."

Sorry, I guess the physics in me just raised it's ugly head. 8)

Göran

 

[butcher]

g_axelsson,
Thanks I fairly well understand what is happening in the process, I do have a hard time putting it into words, a skill I have trouble with, thanks for putting it into words that make more sense, and use of correct terminology.

Dissolving metals with heat. I suppose all of those excited little electrons under that torch, with the hot foot dancing around, are very busy jumping to higher energy levels (or electron shells) in formation of the alloy.

 

[Irons]

I have carried out tests on stainless steel as a jeweller friend advised me of this sort of thing happening. Acids will pass as gold on stainless steel. Practise Filing into stainless steel and (true)18ct gold you will no how different it feels. Also the only magnets i use now as another tests are the magnets from old hard drives. I have noticed some cheap magnets not being strong enough to detect all base metals. There is an acid bottle test i have that distinguishes between platinum and stainless steel.
If you get caught once you will never make the same mistake again.

There are stronger Magnets than those from Hard Drives. Type N 52 Neodymium Alloy seems to be the strongest available. I purchased a few a while back. They are expensive, but will pick up most Stainless Steel. I say most because there is at least one type of Stainless it won't pick up. It's used in Standard Testing Sieves. I don't know what type it is, but it has no detectable effect on the N52 Magnet. On the other hand, type 316 Stainless grabs with a strong pull.
Tungsten has no effect at all on a Magnet. The only way to determine if it is Gold is to use an Ultrasonic Thickness Gage. The velocity of the signal through Gold has a considerable difference, compared to Steel or Tungsten, and will show up as an error in the measured thickness compared to the actual thickness of the item in question. It's a very quick and non-destructive method of testing items. Small handheld units are available for under US $200.

 

[Dan Dement]

Justin,

S.G. test will catch it. I have two Alpha Mirage S.G. Scales and it's at great test for filled bars,, rings, and chains. I have three years buying using an S.G. Scale and using XRF's. It has saved me from making expensive mistakes all the time. I am on my fourth XRF and have sold all the older machines to friends when a new upgraded model came out. When it comes time to cash out, it's useful indication but not as accurate as an good XRF and good masters.

Dan

 

[niteliteone]

Justin,

S.G. test will catch it. I have two Alpha Mirage S.G. Scales and it's at great test for filled bars,, rings, and chains. I have three years buying using an S.G. Scale and using XRF's. It has saved me from making expensive mistakes all the time. I am on my fourth XRF and have sold all the older machines to friends when a new upgraded model came out. When it comes time to cash out, it's useful indication but not as accurate as an good XRF and good masters.

Dan

How does it do with those Chinese bars that have been drilled and filled with Tungsten, then resealed :?:
I've read more than one story of people getting reamed with them from sellers on ebay

 

[justinhcase]

Thanks Chaps ,That is all really helpful
I will have to find or make some relevant examples of Tungsten filled Items and experiment further.
Particular thanks to Irons for the extra help with the ultrasonic velocity method.
I can see it would be a good service to offer to clients as well as use my self.

 

[Tub Buster]

Ultrasonic testing is useful for bars and other standard shapes that can be calibrated.

Gold, stainless steel and tungsten are very different metallurgically. Gold is soft and malleable, stainless is significantly harder, and tungsten harder still.

Probably hardness would be the easiest parameter to test, as most jewelry is curved, and strain differs with geometrical shape. Google "hardness tester". A photo of a tester I use for lead is attached below.
Here are some values from http://www.matweb.com : Incidentally, this is a good site for determining composition of alloys, like dental alloys for example.

Gold:
Hardness, Vickers 25
Tensile Strength, Ultimate 120 MPa 17400 psi Annealed
Elongation at Break 30 %
Modulus of Elasticity 77.2 GPa 11200 ksi 60% Cold Worked
Poissons Ratio 0.42
Shear Modulus 27.2 GPa 3950 ksi
Electrical Resistivity 0.00000220 ohm-cm
Magnetic Susceptibility -1.42e-7
====
Tungsten:
Hardness, Brinell 294 Estimated from Vickers.
Hardness, Vickers 310
Tensile Strength, Ultimate 980 MPa 142000 psi
Tensile Strength, Yield 750 MPa
Modulus of Elasticity 400 GPa 58000 ksi
Poissons Ratio 0.28 0.28
Shear Modulus 156 GPa 22600 ksi Calculated
Shear Strength 400 MPa 58000 psi Average value for W blanks.
Electrical Resistivity 0.00000565 ohm-cm
Magnetic Susceptibility 3.3e-7
==========
316 Stainless steel:
Hardness, Rockwell B 69.5 69.5
Tensile Strength, Ultimate 538 MPa 78000 psi
Tensile Strength, Yield 200 MPa 29000 psi