Metallurgy/Questions Answered by Expert Mel Gaultry
| Subject | Date Asked |
| ABout stainless steel grdae 201 | 10/31/2007 |
| Q: I have a contract with a Chinese supplier FOR IMPORTING stainless STEEL GRADE 201 TO MY COUNTRY ,PLS ... A: I am not an expert in these things, as per my profile, but here are the basic specifications for ... | |
| GOLD! | 10/21/2007 |
| Q: my names Dan Harris, My father run a store which commonly buys scrap gold. I'm very interested in ... A: Actually, there are some very good schools, depending on where you are located. Missouri, Nevada, ... | |
| metallurgy | 10/10/2007 |
| Q: a fine grain steel makes me think of a hardened steel. can a steel be a fine grain steel and be soft A: My apologies for the delay in answering your question. I have been working on a field assignment. ... | |
| gold dental fillings | 10/9/2007 |
| Q: I have about 4 ounces of gold dental fillings. The fillings contain approximately 80% gold with the ... A: Sorry for the delayed response, I have been doing field work away from my office. You certainly ... | |
| gold reduction | 10/7/2007 |
| Q: how much gold concentraction should be in the organic phase(DBC)befor reduction by oxalic acid ... A: It really does not matter the concentration of gold in the DBC, it will respond well to very small ... | |
| Gold Extraction | 10/1/2007 |
| Q: Mel, I have debated using mercury and smelting to extract gold from the almost 250 Kg of samples we ... A: Do you have a good furnace available? If so you might want to consider a lead / zinc separation. ... | |
| gold dental fillings | 10/1/2007 |
| Q: I have about 4 ounces of gold dental fillings. The fillings contain approximately 80% gold with the ... A: Sorry for the delay, I have been out doing field work all week. Do you have a furnace available? ... | |
| gold reduction | 9/30/2007 |
| Q: I work on gold extraction from copper anode slimes, I leached it with aqua regia and then solvent ... A: Your method is fine, but a couple of details might be helpful. You do not have to use full strength ... | |
| Yield strength of metals | 9/29/2007 |
| Q: I am a 2'nd degree black belt that is into breaking. I would like to break a bar like the shoulin ... A: Boy, this is a risky procedure. Bismuth is pretty brittle, but in a heavy bar it is still quite ... | |
| medieval metallurgy | 9/27/2007 |
| Q: I homeschool my children and am doing a few then and now units relating life in the Middle Ages with ... A: Where are you now, time wise? I have been in the field, but am back at home for a week and could ... | |
| Gold Extraction | 9/25/2007 |
| Q: Mel, I have debated using mercury and smelting to extract gold from the almost 250 Kg of samples we ... A: If you have access to a small gold wheel or concentrating table you can concentrate the gold into a ... | |
| Gold Extraction | 9/24/2007 |
| Q: Mel, I have debated using mercury and smelting to extract gold from the almost 250 Kg of samples we ... A: Mercury and smelting don't mix, the fumes are extremely toxic and should be avoided. The centrifuge ... | |
| Separating gold from brass | 9/22/2007 |
| Q: I was wondering what a simple home method for separating the brass from gold would be if any. I ... A: First, I am sorry to take so long in answering. I have been doing desert field work away from the ... | |
| Separating gold from brass | 9/21/2007 |
| Q: I was wondering what a simple home method for separating the brass from gold would be if any. I ... A: I would need to know the approximate percentage of gold in the alloy in order to make a suggestion. ... | |
| post welding heat treatment | 9/16/2007 |
| Q: would you please help me to find a book or article about microstructure of stainless steel 304 ... A: These should provide some answers... Steels: Microstructure and Properties (ISBN: 0750680849) ... | |
| dibutyl carbitol | 9/6/2007 |
| Q: Can you tell me where I can buy dibutyl carbitol in small amounts,like 1 gallon or so. I think Ferro ... A: DiButyl Carbitol is a very useful extractant for gold, especially from mixed acid solutions. It ... | |
| gold work hardening | 8/25/2007 |
| Q: I found that the more they are used the more retentive they become...we assumed the opposite due to ... A: Pure gold will not work harden. High quality gold found in the tombs of Egypt show no evidence of ... | |
| gold refining | 8/20/2007 |
| Q: A friend just bought a cigar box of misc high grade ore samples from the Homestake mine in the Black ... A: You are very much on the right track. Before proceeding, however, are these samples of metal ... | |
| 132KV transformer Phase braded connectios | 8/17/2007 |
| Q: I am working in a sub station in Pakistan , and we ave recently replaced a copper braided Phase ... A: Yes, you should use the correct bolt size in order to avoid the contact "wandering" in the hole, ... | |
| square tube vs square bar | 8/13/2007 |
| Q: is 3/4" square tube weaker than 3/4" square bar as far as bending when put under stress on an ... A: yes, especially if the wall thickness of the tube is not heavy. A bar is always stronger, as there ... | |
| case hardening 303 G&P together with 1020 | 8/2/2007 |
| Q: I would like to case harden an assembly of a 303 ground and polished stainless shaft with a gear of ... A: My apologies, I am a metallurgical chemist, and know very little about these things. I build ... | |
| 100 yr old hard brass | 7/27/2007 |
| Q: I've read that brass work hardens, but have been unable to find info about what causes 100 yr old ... A: This is not really my area of expertise, so before you risk damage to your blades, you should talk ... | |
| aluminum hardness | 7/24/2007 |
| Q: can you tell me in the e-scale hardness, what 7000 series aluminum should be on the min. and max. ... A: 7000 Series aluminum is basically a variant of the following; Component Wt. % Al 90 Cr Max 0.1 ... | |
| Do u have an idea 4 me ? | 7/14/2007 |
| Q: I am an student of material science and Engineering -Industrial metallurgy in Islamic Azad ... A: This is a tough one, as I am not familiar with your local metallurgical issues, but you might ... | |
| welding of low alloy steel(p9) | 7/10/2007 |
| Q: my question is ABT the welding to be carried out on the skirt support of the pressure vessel of the ... A: Sorry, I really can't help you on this, I know very little about welding technology, you might check ... | |
| Separation Techniques | 6/29/2007 |
| Q: Mr. Gaultry, Hello, I was very excited to find your site as you seem to be quite the expert in this ... A: Mass spec will certainly work, but I have found better initial results using x-ray flourescense ... | |
| Separation Techniques | 6/27/2007 |
| Q: Mr. Gaultry, Hello, I was very excited to find your site as you seem to be quite the expert in this ... A: I will do my best to assist... These are all valuable metals, and, under most circumstances easily ... | |
| refining mine material | 6/26/2007 |
| Q: we have a mine in Chile with silver 400 gr. ton , gold 10 grs. ton and others. We want to export ... A: I will check with some contacts in the industry and get back to you, I am on the road so it may take ... | |
| refining mine material | 6/25/2007 |
| Q: we have a mine in Chile with silver 400 gr. ton , gold 10 grs. ton and others. We want to export ... A: Possible? yes, Practical? marginal at best, it would depend entirely on shipping and handling cost. ... | |
| gold | 6/9/2007 |
| Q: How can gold be separated from metal, what is the process? ANSWER: Hi, I can help you with this, ... A: Melting is probably not the answer. Most such gold is plated on the surface and is amenable to a ... | |
| gold | 6/3/2007 |
| Q: How can gold be separated from metal, what is the process? A: I can help you with this, but I need to know a few details, what is your general level of expertise ... | |
| gold casting | 3/27/2007 |
| Q: Sir, What is the difference between plaster used in gold investment casting and ceramic used in the ... A: In general, the plaster used in gold investment casting is standard "plaster of paris" or other such ... | |
| electrical contacts | 3/27/2007 |
| Q: Sorry about the recent death in your family, my condolences. Here is myIn electrical switch ... A: I have processed a lot of electrical contacts. Many older contact sets contained large percentages ... | |
| composite material | 3/23/2007 |
| Q: in the stir casting method which used in composite does the speed of stirring and number of ... A: All of the factors you mention directly affect the amount of energy imparted to the particles in the ... | |
| composite material | 3/23/2007 |
| Q: does the extrusion process for A355 AND A356 alloy effect on the amount of impact energy? A: Yes, it does. I am not an expert in these things, but I do know that the parameters of the ... | |
| sepeartion of iridium,mixed with gold of 10-24 karat | 3/21/2007 |
| Q: i would be glad to know the process or the chemical process involved in sepearting the content of ... A: First, as a note, "Dibutyl Carbitol" and "Diethylene Glycol Dibutyl Ether" are different names for ... | |
| sepeartion of iridium,mixed with gold of 10-24 karat | 3/20/2007 |
| Q: i would be glad to know the process or the chemical process involved in sepearting the content of ... A: I use an XRF all of the time for trace detection of iridium, there are some methods first developed ... | |
| would this work | 3/20/2007 |
| Q: I just plan a project to melt copper wire by using the sun, ok taking the concave mirror and some ... A: in brief, unlikely... copper is an excellent heat sink and therefore hard to melt in this manner, ... | |
| mechanical properties | 3/19/2007 |
| Q: are there mathematically methods to find the porosity in specimen of composite material made by stir ... A: Not to the best of my knowledge, but you can do qualitative porosity tests with compressed air or ... | |
| sepeartion of iridium,mixed with gold of 10-24 karat | 3/19/2007 |
| Q: i would be glad to know the process or the chemical process involved in sepearting the content of ... A: Do you have access to any kind of spectrometer? Also, there are alloy and tramp metals in impure ... | |
| case harden steel properties | 2/21/2007 |
| Q: Does case harden steel properties detoriates over time? especially for guns parts like bolt carrier? ... A: Hardened steel does not generally deteriorate over moderate periods of time, especially not as short ... | |
| Heat transfer ratios | 2/8/2007 |
| Q: My idea is to cool hot liquids (soup or stock) from the center outward does this make sense?Hello, ... A: Yes, that makes sense. If you look closely at the "slush" machines in convenience stores as well as ... | |
| Heat transfer ratios | 2/8/2007 |
| Q: The project is to find a suitable metal for use in the food service industry to assist in the ... A: What are you trying to cool? Solid, liquid or gas (steam) all have differing heat transfer ... | |
| Heat transfer ratios | 2/7/2007 |
| Q: I am working on a project for school. I need to find a metal or alloy that has the best heat ... A: I can help you. A lot depends on your budget. Aluminum is a good start, but silver and gold alloys ... | |
| need help | 2/7/2007 |
| Q: how is metal heavy A: All metals are not heavy. Hydrogen is a metal, and is the lightest element known. Lithium, also a ... | |
| brass | 1/3/2007 |
| Q: what's the melting zone of brass,which Zn% is 15%¡¢20%¡¢25%¡¢30%£¿ A: Melting zone of 15% Zn Brass is 900 - 940 C 30% Zn Brass is 915 - 945 C These numbers are only ... | |
| metals seperation | 12/16/2006 |
| Q: gday there bill, i first must say im a lay person in this field i want to get a true computer ... A: Please excuse the delay in responding, due to a death in my immediate family, I have not been able ... | |
| Reply received? | 11/29/2006 |
| Q: I have not worked with aqua regia before but would certainly be able to safely manage the use of it. ... A: Please excuse the delay in responding, due to a death in my immediate family, I have not been able ... | |
| Separate gold from brass? | 11/25/2006 |
| Q: I recently melted a very beat up gold colored chain marked with 14K. A puddle of bright yellow ... A: A 14K chain should be about 58.3% gold by weight. Gold is easy to separate from brass. Do you have ... | |
| ceramic | 11/23/2006 |
| Q: many thanks for caring about my question, i want you to recommend one simple and most type of ... A: Please excuse the delay in responding, due to a death in my immediate family, I have not been able ... | |
| light weight metals | 11/22/2006 |
| Q: I have an invention, and would like to know if there are metals lighter than alluminum, but with ... A: There are many metallic and composite combinations lighter than aluminum, but not a lot lighter, and ... | |
| ceramic | 11/19/2006 |
| Q: what is the chemical composition of ceramic and what is its atomic density because it is urgent in ... A: There are literally thousands of different ceramic products. They have widely varying atomic ... | |
| strength of stainless steel | 11/6/2006 |
| Q: im in year 11 currently attending metals technology. for an assignment, im stuck on these questions: ... A: There are a wide variety of stainless steels that vary in composition, weight and cost. Most are ... | |
| chrome plating | 10/31/2006 |
| Q: I not completely clear if chrome is just a blueish,hard,clear coating and that the silver is just ... A: Sorry for the delay, I have been on the road on a consulting job. Chrome plating is generally a ... | |
| stainless steel at cryogenic temperatures | 10/21/2006 |
| Q: Is there a possibility of inducing stress cracking in an insulated stainless road tanker vessel (20 ... A: Assuming a two hour load time, insulation in good condition and steel in good condition with no ... | |
| gold recovery | 9/28/2006 |
| Q: When using mercury to recover very, very, fine gold from ore what is the best way to separate the ... A: An interesting collection of questions, is the mercury being mixed directly with the fine ore? A ... | |
| Why does aluminium have to be recycled? | 9/20/2006 |
| Q: I need to find out or research why aluminium has to be recycled (it's part of my homework). Please ... A: The biggest cost by far in the production of aluminum is electrical energy used in extracting ... | |
| Aluminum Piston pin bore galling to piston pin | 9/16/2006 |
| Q: Mr. Bill, I am an automotive engineer. I am presently working on a piston pin bore scuff problem. ... A: sorry for the delay in responding, I have been on the road. This seems to be an unusual situation. ... | |
| separating gold from mercury | 9/15/2006 |
| Q: what would be the best way to seperate gold from mercury? Is there a machine for safely distilling ... A: sorry for the delay in responding, I have been on the road. The separation of gold from mercury is ... | |
| Copper Wire | 8/31/2006 |
| Q: I recently purchased some copper electrical wire from home depot. its about 1/8" diameter wire. I ... A: your problem does not lie with your mini-torch, it is probably working perfectly. Copper is very ... | |
| Metal Hardness | 8/31/2006 |
| Q: I would like to know which are the hardest compounds or metals easily available on the market. Some ... A: There is no commonly available substance harder than a diamond, or even close. There have been some ... | |
| high temperature alloys | 8/20/2006 |
| Q: I would appreciate if u could give me some idea about the types, properties and application of high ... A: There are literally thousands of high temperature alloys. Many are iron based, others are titanium ... | |
| 316 SST and NACE | 7/27/2006 |
| Q: 316 SST bar in the annealed condition - will it always conform to ASTM. A479 and NACE MR0175 ? A: Annealing results in changes to the microstructure of the steel, modifying its strength, hardness, ... | |
| Brass | 7/25/2006 |
| Q: "If" I could make a flat brass plate, how could I record a message on it? Are there any known brass ... A: There are many varieties of "brass", some softer thn others. Historically, brass is a rather soft ... | |
| stainless steel | 6/21/2006 |
| Q: I am developing a new product that will cook food on a charcoal grill on stainless steel grates. ... A: I would think that 316 would be a better choice, it has better corrosion resistance at high ... | |
| Gold and aluminium seperation | 5/24/2006 |
| Q: Yes me too. We have to make a living. I am just about out of dibutyl carbitol. I have to reorder ... A: The separation of gold and aluminum is largely trivial. The reason that there is not more ... | |
| Gold and aluminium seperation | 5/14/2006 |
| Q: Sorry for the delay but I didn't receive any email reply. This is the first time I have used this ... A: Sorry for the delay, I am on the road, but will be back at my office in Monday. In the meantime, do ... | |
| Gold and aluminium seperation | 4/13/2006 |
| Q: Firstly, thank you for the quick response. About a 500g batch of material at the moment. Smallest ... A: OK, don't try to use the halide system for this project, there are some potentially dangerous ... | |
| Gold and aluminium seperation | 4/13/2006 |
| Q: I have numerous aluminium items that have been coated with a thin layer(2-7micron)of gold. ... A: Not as difficult as you might think. I need a little more data, how much material are you talking ... | |
Mel Gaultry
Top Expert on this page
Expertise
Questions regarding the extractive metallurgy of precious metals including gold, silver, platinum, palladium, rhodium, iridium, osmium, ruthenium as well as questions regarding the analysis of raw materials for content of these metals (assaying) Please note that I can not perform actual assays at this time. Please note that I do not claim expertise in structural metallurgy pertaining to steel, brass, etc. I will do my best to assist in such matters, but it would not be fair to represent myself as an expert nor should I be rated as such.
Experience
Past/Present clients
Inco, Alcan, PD, Falconbridge and many small independent operators
©2012 About.com, a part of The New York Times Company. All rights reserved.