Sivadharshan SRD - 24-6-2025 at 06:24
Hi guys, I used to work with gold on professional side and in that process I used to cut gold using laser.
Fumes coming at that time are actually gold.
I need best ways to collect that gold without any major loss of the weight of the gold as fumes.
And from the method I used to collect, I obtain it as powder or dust form of gold almost purple gold in colour (but not pure gold) how can I get it as
either solid or pure solid gold without any loss during melting process- what are the ways can I use for melting and purifying
bnull - 24-6-2025 at 07:19
Welcome to the forum.
In all chemical and physical processes there will always be some loss. That's essentially unavoidable. The way to recover as much gold as possible,
given the losses as (invisible to the naked eye) fine dust and vapor, and in the purest state is electrolysis. For example, you can dissolve your gold
dust in aqua regia and use the Wohlmann (or Woolworth or Wohlhill, I forgot the name) process to recover it from solution.
Do you know how much (percentage seems good) gold is lost during the cutting process?
Edit: grammar.
[Edited on 24-6-2025 by bnull]
Sulaiman - 24-6-2025 at 08:55
if not secret, approximately what quantity is involved ?
eg very small quantities are best processed in very small vessels,
patiently waiting for sediment to settle followed by careful decanting vs. filtering etc.
refining can be via wet chemistry, or metalurgy, or a combination of both,
If you want a solid piece as your final product then you will need to melt gold.
If you go the wet chemistry route, be aware that very finely powdered metals react much more rapidly than larger particle size powders,
often violently.
My electrochemistry and electroplating (not with gold) experiments have pretty much all failed in some way or other so I can't comment.
The good thing about gold is that it is an element,
so do not dispose of any solids or liquids until you are happy with your yield.
If you do not get all that you expect, don't worry,
the 'missing' gold is in one or more waste containers and will not be too difficult to find and recover.
I like watching https://m.youtube.com/@sreetips/playlists
PS because I like the chemistry of gold I would probably;
dissolve the powder in aqua regia, neutralise any nitric acid, add a few drops of sulphuric acid to precipitate metals like lead, filter or decant,
SO2 or SMB to drop the gold.
(So far, the more concentrated the gold solution the larger the particle size)
after washing you will have fairly pure powder suitable for melting.
[Edited on 25-6-2025 by Sulaiman]
RU_KLO - 24-6-2025 at 10:11
use a vacuum pump (or any aspirator) with some washing bottles in front.
The idea is that you suck the fumes, which are washed in the washing bottles and the gold keep there.
the chemicals inside de washing bottles are for you to decide. (maybe some cyanide - inform you better before using cyanide or cyanide related
chemical, because you can easily die.)
I do not know gold chemistry, but found this document with a lot of information, where you can search which chemicals to use and process.
https://www.saimm.co.za/Conferences/ExtractiveMetallurgyOfGo...
Attachment: extraccion de oro 0831-Chapter15.pdf (3.3MB)
This file has been downloaded 116 times
Radiums Lab - 24-6-2025 at 11:59
Welcome to SM,
Could you please elobrate or tell us what method you are currently using to collect the gold fumes produced and how are you processing them so that we
could help or suggest a better alternative.
Pictures would make this more easier.
Sivadharshan SRD - 24-6-2025 at 20:08
Hi guys thank you for your response,
I use vacuum suction based cyclone collector to collect gold which are liberating as fumes and by my quantitative analysis around 65 to 70 percent of
gold is collected which are liberated as fumes but I know that it can be pushed to upto 85 to 90 percent because I have seen some others getting that
much.
Small utensils are best for small quantities and actually it is a process of collecting that takes months to see a good amount of gold like 30 grams
in 3 to 4 months (it varies based on the work we get) but approx at present is this.
The thing is I need best ways to melt that powder without any loss in melting process and what can be the suction power of vacuum should be to collect
a promising amount of gold.
I think my vacuum motor I am using currently is overpowered, can I use two cyclone collectors in series to reduce that loss.
Sorry guys I don't have pics right now
I will send it during my next post
Thank you.
just a quick calculation...
Sulaiman - 24-6-2025 at 22:12
30 (g) /(3 to 4 months) x 100 (usd/g) x 12 (months per year) = 9,000 to 12,00 (usd/year)
you expect to increase your yield from (65 to 70 percent) to (85 to 90 percent),
about a 30 percent increase.
So, your investment in the improved collection system should cost less than 2,700 to 3,600 (usd per year) to be profitable.
you could try melting your powder in a small graphite crucible with lid,
just to get a blob more suitable for metalutgy etc.
eg
https://www.ebay.co.uk/itm/284772440013
Radiums Lab - 25-6-2025 at 04:21
Yea you could melt your gold in a closed graphite crucible as Sulaiman suggested and use borax to get a perfect blob which does not stick to the
containers wall.
Eithern - 15-7-2025 at 12:37
If I understood correctly, could you put a paper filter after the cyclone to collect even the finest particles, and then burn it in a crucible and
melt the gold?
Sivadharshan SRD - 16-7-2025 at 08:04
Thanks for replying Eithern
I have tried for paper filters but I couldn't find any proper one that fits to the setup and also which can withstand the suction power. Once I tried
with a custom made one but there was not much gold could be recovered from that and also it reduces the suction power rapidly, continuous running on
that setup made the motor to repair.
That's why I came up with the idea of double cyclone
And sorry guys for not posting any images since I can't open the cyclone frequency as the gold dust can fly over and it was emptied at the time of
this post was created
I will try to send the images soon