The Calcium Curse — why a tungsten skarn fights back at the mill
Updated: Sep 17
In the previous Samso Insights - Understanding Tungsten - Part 1- "Reading the Skarn — where tungsten hides in the contact", calcium was the hero: it trapped tungsten as scheelite and built the orebody. In this discussion, it becomes the villain. The same calcium leaves scheelite surrounded by look-alike minerals — calcite, fluorite, apatite — that are almost impossible to tell apart in a flotation cell. This is why a high-grade skarn can still be a hard business.
Samso Insights | Research Note | Understanding Tungsten - Part 2 | Geology Series |
WHAT THIS PIECE COVERS 1.00 WHY THE EFFORT IS WORTH IT Tungsten in sixty seconds, and why anyone bothers with the difficulty. 2.00 WHERE TUNGSTEN LIVES - RECAP Four deposit types, and why skarns lead. The calcium curse, stated in one idea. Getting from 1 per cent rock to a 65 per cent concentrate. Physics first, gravity and magnetism. Why flotation is unavoidable, and how it works. Collectors, and what makes them grab the scheelite. Depressants, and what holds the gangue down. The Petrov process, a 1940 answer still in use. The same problem, solved differently at every mine. Greener chemistry, and computers taking on some of the guesswork. 12.00 SAMSO CONCLUDING COMMENTS So how do you actually treat a tungsten skarn? |
1.00 — WHY THE EFFORT IS WORTH IT
Tungsten in sixty seconds
Before the challenge of processing, comes the reward. Tungsten stands out in metallurgy due to its exceptional properties: it has the highest melting point of any metal and a density close to that of gold. This makes it a preferred choice for cutting tools, armor, and aerospace applications. Additionally, tungsten is rare, difficult to recycle, hard to replace, and approximately 80% of it is sourced from China. This is why the EU considers it a critical raw material.
