Infill vs Alteration

[@richardhaselwood9478]

The shots fired at the engineers was gold! 😆

[@GeologyUpSkill]

In-coming!

[@billwaterson9492]

An orbital strike, some would say.

[@cristianbenites4521]

Simple. Concise. Memorable. Thank u future collegue!!!

[@GeologyUpSkill]

Thanks Cristian. If your future career is assisted by my video. Then I did good today!

[@trevorwhat]

That’s the cleanest explanation I’ve ever heard. Big thanks.

[@GeologyUpSkill]

It is my mission to break down the complex bits of geology into clear, concise explanations. Thanks for you comment :)

[@phoratio]

Love the explanation for the engineers.

[@GeologyUpSkill]

;)

[@HeadakusMaximus]

I love these little updates/refreshers! Such a good example as well.

[@GeologyUpSkill]

Thanks very much. It's the little clear answers that I see in rocks every day that keep me motivated to go out tomorrow!

[@paulw3182]

Great Video, graphics and the rock sample were perfect.

[@GeologyUpSkill]

Thanks Paul. That animation took quite a while to build even though it looks simple. I am a better geologist than animator!

[@cribbsprojects]

Always golden information in a very small vein of video! Every time I watch one of these, I am more and more tempted to pay for the long story!

[@GeologyUpSkill]

Thanks very much. Every time I read a comment like this, I am more and more tempted to get serious about marketing, but I just love rocks too much!

[@AEVMU]

So much good simple info! I have forgotten most of my geo training and its fun to come back to it!

[@GeologyUpSkill]

Rocks are fun. That's why I do this :)

[@talathussain5078]

Sir I am a Geologist. I am working in a Government organization. I was assigned on some clerical jobs. I resisted,I told them spare me as a Geologist,but they were obstinate. I had to capitulate, keeping in view the job market for the Geologist.After twelve years I was asked to work again as a Geologist. I had almost forgot Geology. Then I turned to KZbin to learn as much as I could. Here I found your videos. I am making notes what you are teaching. It helps me a great deal. I know it will take a few years to catch up on. But, I am willing to do it. Thank you so much for your efforts, and help. There are thousands of books. But Geology can only be learnt in the field, clearly. Thanks again. 🙏

[@GeologyUpSkill]

Many thanks. Your comment and others like it will inspire me to make more!

[@vitorribeirosa]

Amazingly explained. Thank you very much for sharing this content and your experience. I have shared this class with my labmates. Cheers!!!

[@GeologyUpSkill]

Thanks Vitor. I try to make videos that make concepts crystal clear. :)

[@bilalakram2101]

short,precise, clear and concrete...

[@GeologyUpSkill]

And so fundamental to understanding ore systems, it should be taught on the first day of every economic geology course!

[@welmercanto4772]

This is very informative as a geologist. Thank you.

[@GeologyUpSkill]

Thanks Welmer. I try to put useful information in each video.

[@northeast6414]

Thank you for this video and all the others. I am a hobby gold prospector and the more I learn about geology, the more I realise I don’t know. Your videos are assisting in a short, accurate and generally humorous manner. So thanks 😊

[@GeologyUpSkill]

I love geology precisely because you can never know it all. There is something new to understand every day.

[@galatura]

Great Presentation, excellent !

[@GeologyUpSkill]

Thanks Galatura. Much appreciated.

[@linglinzhong5585]

Amazing video! I have learned a lot about the specific knowledge and how you explain it.

[@GeologyUpSkill]

Great! That is the main aim of my videos.

[@ouaskioudkhalid6659]

Fascinating video, thanks professor

[@GeologyUpSkill]

Thanks Ouaskioud. It's a simple, but very useful concept to keep in mind when you are trying to unravel hydrothermal mineralization systems.

[@jdean1851]

EXCELLENT" DETAILS!!! THANKS"

[@GeologyUpSkill]

Thanks. It's a simple concept but so important in understanding hydrothermal ore systems.

[@carlinlentz6849]

One comment I have is that the alteration could predate the vein infill by a significant period of time (1-10 Ma). This isn't always the case, but often the structures that fluids travel through are active over a very long period of time. Example would be a fault structure that contains antimony mineralization and silicification of surrounding wallrocks that contains a large amount of fault gouge that surrounds it. The fault that allowed for the emplacement of the antimony mineralization (extensional) may have changed structural environments over its life cycle.

[@GeologyUpSkill]

That is correct, and structures that have had multiple episodes of activity are much more likely to contain orebodies that single event systems. There is much to be learned by sitting on old ore dumps and figuring out the paragenetic sequence of events from all the free samples on the pile!

[@TheShivermetimbers10]

​@@GeologyUpSkillexcuse my lamens terms, but hypothetically, could this include flourite forming within limestone, the limestone dissolving while the less reactive flourite remains and over time a new mineral/rock forms around the older flourite minerals?

[@kaciageorge73]

Amazing explanation! ❤

[@GeologyUpSkill]

Thanks Kacia. Glad it helped you understand the concept. I use it every day in the field.

[@twisttwister8254]

Always learning from u. Thanks 🎉❤

[@GeologyUpSkill]

Thanks for taking the time to comment. I'm glad you found something useful in the video.

[@alsirabdalla1112]

amazing description

[@GeologyUpSkill]

Thanks. Glad you found it useful. :)

[@yanwarissakof1109]

Extraordinary 🙏🙏

[@GeologyUpSkill]

Thanks. It's a simple concept, but very useful!

[@mustafa_mohammadpoor20]

Flawless 👌

[@GeologyUpSkill]

Thanks Mostafa.

[@carlinlentz6849]

A reverse example for the sample you are showing would be gold-bearing arsenian pyrite and arsenopyrite in carlin-type or carlin-like gold deposits. The alteration of wallrocks precipitated gold-bearing sulphides and the infill quartz-calcite-ankerite veins and veinlets contain no gold at all!

[@GeologyUpSkill]

Yes, carbonate replacement deposits (including Carlin, skarns and MVT) are the exception that proves the rule, although for Carlin type you could argue that the precursor decalcification event actually creates open space on a micro scale for the ore minerals to precipitate.

[@DCGMI-b3l]

Amazing explanation Sir. just 2 questions: You said ''this is half an ounce''. Is it for this specimen precisely or is it about the grade per tonnage in general? Also , Is it possible to find lots of these piece of rocks with these infill in dumps ,in order to recycle them to extract some gold out of them? Thans you Sir for your amazing work

[@GeologyUpSkill]

The grade is per tonne in general from historical records. There are quite a few pieces scattered around, but setting up a processing facility appropriate for this ore would probably cost more than you could collect.

[@DCGMI-b3l]

@@GeologyUpSkill Understandable now, thanks you for reply Sir

[@javieratorresromero8038]

your channel is everything! thank u sooo much

[@GeologyUpSkill]

Thanks for commenting Javiera. Every person that takes the time to comment motivates me to produce more useful videos :)

[@geradkavanagh8240]

That was classic example. Hard to find in many areas of Australia where water has slowly (over hundreds of thousands of years) dissolved a lot of trace items. Leftover material on bedrock sometimes has this .

[@GeologyUpSkill]

Yep. This was a piece of discarded ore from a mine below the water table.

[@geradkavanagh8240]

I'd love to find a spot where this was showing.

[@geradkavanagh8240]

Have to meet up someday. Your very good and I could throw some assumptions at you which may lead to discoveries. I worked with other geologists in the coal mining industry, Some had great success and ended up millionaires. Some just floated along and made a lot anyway.

[@phaithoonvongsinery893]

Very interesting​ rock

[@GeologyUpSkill]

A good example. That's why I made a video!

[@Felipe-yh6ct]

In the paragenesis, the sulfides and quaertz are syn genetic?

[@GeologyUpSkill]

Those minerals are infill in breccia so they are certainly epigenetic.

[@Felipe-yh6ct]

@@GeologyUpSkill Sure, but in the alteration paragenesis, is quartz first and then sulfides, or both occur at the "same" time?

[@lemiwakjira8680]

Thank you a lot sir👊👊

[@GeologyUpSkill]

Thanks for taking the time to comment Lemi.

[@marklexus27]

Can we call the alteration predominantly with pyrite as pyritization?

[@GeologyUpSkill]

Yes, but pyrite is a component in many different alteration assemblages. Identifying the associated silicate minerals in the assemblage will give some useful information about the type of hydrothermal system that you are dealing with.

[@lachlanscanlan5621]

"this'll go half an ounce" ha ha lets admit it, we all love gold

[@GeologyUpSkill]

Actually that is probably a conservative estimate in this case!

[@lachlanscanlan5621]

@@GeologyUpSkill yeah Nick it looks great, a nice ore specimen and even the casing is jam packed with sulphides just for show!

[@Sharon_6i]

Whoops! A system error led to the transaction being sent to an invalid email.

[@GeologyUpSkill]

That sounds more like a scam than a system error.

[@independent9245]

😀

[@glenwarrengeology]

Ah Engineers, the disappointment to have met some lil.

[@GeologyUpSkill]

We love to hate them and the feeling is mutual!