Do you know about metal recycling? Learn about the recycling of gold, platinum, and other high-value metals.
I am Fujimori, a craftsman at MITUBACI.
Today, I would like to talk about the metals we recycle at MITUBACI.
The metals that MITUBACI currently handles are 925 silver, K18 gold, and Pt950 platinum. It would be nice if all the metals we purchase could be turned into products, but inevitably they are reduced in the course of processing, such as silver used for practicing metal engraving, gold and platinum scraps used for handmade wedding rings and handmade engagement rings, and metal shavings from files.
Silver, gold and platinum are very expensive metals. Therefore, we collect and recycle as much of the reduced amount as possible. Not only visible metal lines, chunks, and files, but also abrasive dust from polishing with buffing motors contain silver, gold, and platinum, so we collect and recycle them as much as possible.
![](https://www.mitubaci.co.jp/wp-content/uploads/2021/02/IMG_3575-768x1024.jpg)
Metal recycling of large scraps and chunks
![](https://www.mitubaci.co.jp/wp-content/uploads/2021/02/IMG_5286-1024x768.jpg)
Here is the silver used in practice by a customer who came to the workshop.
Thanks to you, there's plenty to go around!
Large visible scraps or chunks of silver, like the silver plate used in practice, are collected and melted at MITUBACI and made into silver plate material again. The material is used as workshop material or as practice material for making wedding rings in gold or platinum.
Gold and platinum scraps and lumps are also separated into the same type of gold and platinum, collected and melted. The melted metal is then processed into a wire shape that is easy to use for MITUBACI products.
Recycling of fine, powdery metals
Powder from filing rings and abrasive powder from polishing rings with buffing motors are a mixture of various metals and impurities. Therefore, they cannot be dissolved and used as is.
![](https://www.mitubaci.co.jp/wp-content/uploads/2021/02/IMG_4534-1024x768.jpg)
The recovered impurity-bearing precious metals are first incinerated at high temperatures to remove dust and other non-precious materials.
The king of water that dissolves everything
After being incinerated, they are placed in a liquid called ohsui (royal water). Ohsui is a 3:1 mixture of nitric acid and hydrochloric acid. It is a liquid with very strong oxidizing power and can dissolve most metals, including gold and platinum.
King's water dissolves everything, but silver is almost insoluble in king's water. Silver is dissolved in nitric acid.
The melted liquid is recycled (recycled) as precious metals by electrolysis or chemical treatment to refine it into pure silver, pure gold, pure platinum, etc.
These procedures are difficult to perform in a workshop, so we ask a specialized company to perform them for us.
When used at MITUBACI, the newly reclaimed precious metals are processed in the workshop into long, thin sheets called wire rods. This is used to make rings and bangles.
![](https://www.mitubaci.co.jp/wp-content/uploads/2021/02/IMG_6772-1024x768.jpg)
Silver, gold, and platinum are collected and recycled again, no matter what form they are transformed into, such as small pieces or powder. They are then reborn as shiny jewelry again.
![](https://www.mitubaci.co.jp/wp-content/uploads/2020/11/top_pc-1024x501.jpg)