Golden Science

Did you know that one of the key materials used in thermoelectric cooling modules is bismuth?

In this image, you can see a Peltier module on a lab bench, next to a sample of metallic bismuth.

Peltier modules use the thermoelectric effect to create a temperature difference when a direct current (DC) is applied. One side gets cold, while the other becomes hot. This makes them useful in mini-refrigerators, scientific devices, portable coolers, and custom lab equipment.

But what's the secret behind this effect? It's the unique combination of materials like bismuth telluride (Bi₂Te₃) that enables efficient heat transfer under voltage. Bismuth plays a critical role in conducting electrons and maintaining thermal balance.

So, bismuth isn't just a heavy metal — it's a smart, high-tech material used in cutting-edge applications.


#Bismuth #Peltier #Thermoelectric #Electronics #Cooler #LabTech #Physics #MaterialScience #DIYTech

3 months ago | [YT] | 21

Golden Science

Why Sometimes Gold Is Present but Does Not Precipitate

When ore or soil is dissolved in aqua regia (a mixture of nitric acid and hydrochloric acid), and a positive result is obtained using stannous chloride (SnCl₂) — indicated by purple, brown, or black coloration — it confirms the presence of gold ions in the solution.

However, in some cases, adding common reducing agents such as zinc (Zn) or sodium metabisulfite (Na₂SO₃) fails to produce a visible gold precipitate. This issue often arises because gold forms a stable complex ion in aqua regia, known as tetrachloroaurate: [AuCl₄]⁻. If excess nitric acid remains in the solution or the pH is not properly adjusted, this complex remains highly stable and does not reduce easily to metallic gold.

In such cases, a white, gray, or sometimes purple haze may appear in the solution. This is not a failed reaction but rather the formation of colloidal gold — extremely fine particles of gold suspended in the liquid phase. These particles are too small to settle and remain dispersed, making the gold appear as a cloudy solution instead of forming solid precipitate.

Chemical Example: H[AuCl₄] + weak reducing agent → Au⁰ (colloid) + HCl + byproducts

To resolve this and achieve visible gold precipitation, the following steps are recommended:

Completely neutralize the remaining nitric acid using a neutralizing agent such as urea or by gentle heating.

Add a small amount of hydrochloric acid to maintain chloride ion concentration and stabilize the gold complex.

Add sodium chloride (NaCl) or ethanol to destabilize the colloid and promote coagulation (flocculation) of the gold particles.

Then proceed with reduction using zinc or sodium sulfite to obtain metallic gold as a visible powder.

In conclusion, if the gold test is positive but no metal precipitates, it does not necessarily mean that gold is absent. It may be present in colloidal form, requiring proper treatment to be recovered successfully.

#goldstone
#gold

3 months ago | [YT] | 60

Golden Science

Hey friends!
Hope you're all doing well.
I discovered a method for extracting gold from even the lowest-grade soils about two years ago. In this method, gold actually precipitates as pure metal, and it’s much cheaper and more efficient than traditional techniques.
I had set this method aside for a while, but recently found the formulas again in one of my old notebooks — and I’ve started reviewing them.

It looks like it might take about three to four months to fully refine the method and fix its weaknesses. But honestly, it’s going to cost me quite a bit to complete.

I'll also be removing some of my older low-quality videos and might replace them with fresh content.
Thanks so much to all of you for your continued support! 🙏✨

3 months ago | [YT] | 84

Golden Science

🌟 Thank You for Your Support 🌟

Dear friends,
I sincerely appreciate everyone who has subscribed and supported this channel.
Your likes, comments, and kind presence truly mean a lot to me. 🙏✨

If you haven't joined yet, I warmly invite you to subscribe and be part of our growing community.

📘 A valuable educational PDF will soon be shared exclusively with YouTube channel members as a special gift.

Let’s learn and grow together.
With respect and gratitude,
Your friend, Esfandiar 💛

3 months ago | [YT] | 38

Golden Science

Dear friends,🌺🌺
I've seen some comments where a few people said that I don’t share the names of the chemicals used just to get likes and comments.

Please let me clarify: in some experiments, I avoid mentioning the names of harmful chemicals out of ethical responsibility. However, in videos that involve safer substances, I do provide the names.

Also, please understand that this channel earns an average of only $100 per month, while I spend much more on purchasing minerals and chemical materials. That small income doesn’t really help cover the costs.

Recently, due to a gas cylinder explosion, my lab was severely damaged, and I might not be able to create new videos for a while.

I sincerely thank all of you for your continued support.

3 months ago | [YT] | 46

Golden Science

Gold stone :
Dear channel members,
Here are some upcoming videos currently being recorded and edited:

Testing mineral ore using cyanide — including extraction and precipitation of elements in cyanide solution.

Testing mineral ore using thiocyanate — including extraction and precipitation of elements.

Extraction from cyanide solution using electrolysis — converting directly to metallic gold.

These videos will be exclusively for members.

Technical Notes:
Some questions in the comments asked about the difference between gold sulfide and pyrite, which I will explain in detail.

Pyrite consists of sulfur and iron.
Sulfides consist of elemental ions combined with sulfur — for example: gold sulfide, mercury sulfide, rhodium sulfide, and so on.
Most elements in the periodic table can form sulfide compounds.

When you see various beautiful colors in a mineral sample, it usually indicates the presence of different elemental ions.
Many future experiments will focus on this topic.

3 months ago | [YT] | 75

Golden Science

Hello dear friends,I want to sincerely thank those of you who joined and supported this channel from the very beginning — even when the video quality was low. Your support is now beginning to bear fruit, and extensive research is currently underway.

In the upcoming high-quality videos, I’ll be showcasing a wide range of elements along with the proper and efficient ways to extract them. These experiments are intense and time-consuming, and I’m deeply involved in the process.

Here’s what I’ve prepared especially for the members of this channel:


1. Extraction of elements from sulfide minerals

2. Extraction and refining of antimony into ingots

3. Low-cost and accessible methods for gold recovery

4. Element extraction using cyanide methods

5. Extraction of gold, silver, and copper through induction melting

6. Special tutorials for beginners, including free educational handouts ...and more exciting content to come.

4 months ago | [YT] | 44

Golden Science

Electrolysis in gold extraction:

Dear friends of the channel,
This is a single-cell electrolysis system.
With this setup, it's easy to precipitate gold chloride or cyanide gold at the cathode.

A voltage of 5 volts and 10 amps is suitable for this cell.
You can also use 30 or even 40 amps without any problem.
In fact, using higher amperage can help prevent your power supply from overheating, especially when the concentration of the electrolyte is high.

If you're using this method to extract gold from mineral ore, it's best to use a clean iron electrode as the anode.
If your goal is to recover pure gold, then using a gold anode is preferred.
For the cathode, you can use copper or titanium plates.

One important note: using neutral materials like graphite as electrodes is not always suitable for all electrolysis conditions.
I’ll be discussing this issue more deeply in future videos.

Thank you so much to everyone who likes and comments on the videos.
I sincerely appreciate your support!❤️

4 months ago | [YT] | 42

Golden Science

Dear friends,

In this post, I’m introducing a simple design for a gas furnace used for melting ore. This type of furnace uses thick iron sheets as the main chamber. Since iron melts at much higher temperatures, using 15 mm thick iron plates makes this furnace suitable for reaching internal temperatures up to 1500°C.

The image shows the components in order:
1. Flame outlet – Its diameter may vary depending on the size of the furnace.
2.ron body – The main structure.
3.Base – To hold the furnace securely.
4.Molten metal outlet – A small outlet that allows the melted elements to flow out.

Important Note:
If your ore contains lead, zinc, or gallium, these will melt and flow out before gold, silver, or copper. So, separate the first molten materials to avoid contaminating your gold again.
5.Thermal insulation – You can wrap this around the furnace from the outside to conserve heat. (I also recommend using temperature sensor modules.)
6.Combined gas and air inlet – Using gas without proper airflow won’t reach the necessary temperature and may cause poor combustion.
7.Iron chamber – For placing the prepared ore before melting.
What is “prepared ore”?
It’s ore that has been ground finely and mixed with charcoal and sodium bicarbonate.

✅ Advantages of this design:

Separation of low-melting-point metals early in the process

No need for acids

❌ Disadvantage:

Requires gas for operation

4 months ago | [YT] | 18

Golden Science

Dear friends,
Most mineral deposits are found in sulfide form. Many metals exist as sulfides — like gold, silver, mercury, copper, and many other elements from the periodic table. I'm currently running experiments to ensure the results are accurate, and I’ll be sharing my findings with you soon.

4 months ago | [YT] | 37