Learn How to Test Mineral Hardness Using the Mohs Scale

[@99Rockhounding]

Very informative video Rob. It's funny that Moh's name is a perfect acronym for "Measure Of Hardness". It's like he was born for one purpose.

[@MichiganRocks]

I never thought of that. How cool!

[@perplexedpapa]

That's how I was taught to remember it.

[@80sunshine21]

Looking forward to seeing Joseph running on the beach picking up rocks!! AZ USA

[@MichiganRocks]

Me too!

[@gwynnfarrell1856]

Excellent lesson on the Mohs scale! It was great to have the examples all lined up. The information contrasting glass and quartz was interesting. Thank you for this very enjoyable video! And thank you to your family for participating.

[@MichiganRocks]

I'm glad you liked it, Gwynn!

[@sparband]

That was an interesting video. Joseph is getting so big already. I love that he has already started his Michigan t-shirt collection.

[@MichiganRocks]

He has three so far. That's a good start.

[@tigerg3761]

That little guy is going to have a ton of fun and great experiences going out with dad and grandpa hunting rocks when he gets older!

[@MichiganRocks]

I sure hope he enjoys it!

[@bluetickbeagles116]

Too bad the mum will miss out. I hate seeing women miss out on the more exciting things of life due to kids. 😞

[@davidhile5363]

Very informative. A big thank you to David for the demonstration ! One of these days I can see Joseph paddling along side Grandpa in a kayak ! In industrial settings manufactured diamond tipped tools are used to true, and form angles and radii on carborundum and aluminum oxide grinding wheels. I have a beautiful Petoskey handled pocket knife that my daughter got me for Christmas. It’s stored on my dresser top in the bedroom because I know what will happen if I carry it around in my pocket !

[@MichiganRocks]

I always thought Petoskey was a strange choice for knife scales. Now puddingstone on the other hand could be really nice. One of these days I need to try my hand at making some.

[@SherryAustinMcginley]

Thanks Rob and David! Interesting information 👍 Thanks for letting us see Allison and Joseph 😁

[@ROCKINWHEELERS]

BEAUTIFUL FAMILY, AND THE LITTLE ONE IS SO CUTE!!! BLESSINGS ON ALL!!!

[@jimknarr]

One of your best tutorials! Simple and to the point. I loved the way David took common household items to do a Mohs test.

[@MichiganRocks]

I’d say thanks, but David did all the work for this one. I’ll have to ask him back for another video, I guess.

[@AlkA]

@@MichiganRocks I hope you ask him back for another video I understand exactly why did you invite him in the 1st place 😅😂

[@wyomingadventures]

I'm glad I noticed I missed this video. Very informative video from your son in-law. I've wanted to learn about this. Please tell him thank you. He explained the Moh scale in very easy way for everyone to understand. Cute grandson Rob!

[@MichiganRocks]

I'll let him know!

[@Indyanas_ocean_view]

Awwww Joseph is so cute! 💕💖 Amazing video, very informative! You have spectacular family!😇🥰😍👍🏻👍🏻👍🏻😇🥰😍👍🏻👍🏻👍🏻😇🥰😍👍🏻👍🏻👍🏻😇🥰😍👍🏻👍🏻👍🏻

[@MichiganRocks]

Thanks, Indyana.

[@Indyanas_ocean_view]

@@MichiganRocks Your welcome! 😍🥰😇👍🏻👍🏻👍🏻

[@mbbuckeyes8386]

Your family is so cute and the baby! Handsome. Interesting presentation with your geologist son-in-law. 👍😊. Go Bucks!!

[@stephaniem839]

Oh wow! Super helpful and informative video. So interesting! Thank you!!

[@emdee7744]

Cool! Very informative. I appreciate, as has been mentioned, the explanation of the distinction between quartz and glass.

[@MichiganRocks]

I hadn’t realized that before either.

[@KatyDidRocks]

I love at 11:30 when he's just nerding out about whether one quartz will scratch the other one. Great video, Rob!

[@MichiganRocks]

You sound kind of rock nerdy yourself, Kate. This is where the nerds congregate.

[@ccccarriemchardy9216]

Good information to have, thank you.

[@dancrites453]

That was great! Very educational & entertaining. Thank you...

[@TrueNorthLocks]

The thumbnail is too cute and funny. Love the videos, my husband and I just got into tumbling and your videos are so helpful. Thanks!

[@MichiganRocks]

The thumbnail was David's idea. It's weird and I like it.

[@markattardo]

Awesome info, thank you👍👍

[@horacepierce9210]

I really appreciate the practical explanation of the Mohs Scale. If this topic is used in a future video, I would add one important point that isn't obvious, which is that he Mohs scale is not meant to be mathematically proportional. That is to say that an 8 on the Mohs scale is not twice as hard as a 4. So, a graph of absolute hardness would not be linear, and a diamond (10) is several orders of magnitude harder than a rock that hits the scale at a 9.

[@MichiganRocks]

Thanks Horace. I realize that, but we forgot to mention it. If I ever do another video on this topic, I'll try to remember to include that information.

[@I_wish_I_knew_something]

Your daughter hit the jackpot, a Geologist. Thank you David.

[@MichiganRocks]

They met at church too, that’s even better.

[@TheWonderwy]

Beautiful family.. Thanks David. I enjoyed learning from you and hope to see you back again soon teaching us more!

[@patriciamckean4186]

Congrats grandpa...the scale has helped me identify a rock many times.

[@ruthchapman3847]

Excellent video, reading about testing and seeing the info cement the knowledge in my brain

[@MichiganRocks]

I’m glad it was helpful, Ruth.

[@paigelee6321]

Awesome information, thank you for sharing, always learning about stones, 😊💙grandson is adorable 🥰

[@perplexedpapa]

Great video! This has always been important when sorting my stones for polishing. I had to learn that the hard way, many, many years ago.

[@MichiganRocks]

That's funny because I never test for hardness when tumbling. I almost always use a vibratory tumbler which may be much more forgiving, but I get pretty consistently good results. I do make sure to keep really soft stuff separate, like Petoskey stones and other limestone fossils, fluorite, and obsidian. I don't test those, I have just learned that they're soft. Most beach rocks just all go in together though.

[@sharonbaxter9233]

cool , thanks David for the demo.👍

[@LadyYoop]

This is just awesome. Rocks run in the family blood..how cool is that!

[@MichiganRocks]

It’s pretty darn cool.

[@LadyYoop]

@@MichiganRocks That is so phenomenal...that tradition shall carry on! I love it!

[@jneihart2]

Excellent class gentlemen!

[@MichiganRocks]

Thanks!

[@paleocat6354]

Wonderful video! Congrats on the grandkid!

[@MichiganRocks]

Thanks, Darth.

[@milesnn]

Awesome family great video good knowledge and hands on awesome cute little guy another great video thank u

[@MichiganRocks]

No problem, Miles.

[@rosalindhendricks6337]

Enjoyed this segment with your family and gained some useful information.

[@debs_wheels]

Thanks for the lesson and the Joseph sighting. I’m glad to see he is properly attired in Michigan garb already. Someone needs to invent a “Swiss army MOHS tester”. Something that fits easily in your pocket, has a selection of hardness testers and won’t poke you like a nail or broken glass.

[@MichiganRocks]

They do make something like that. It's not in a Swiss Army knife form, but it comes in a little case. I have never used one, so I can't recommend it, but here's one I found on Amazon. It's an affiliate link, so if you use it, I make about a two percent commission. Doesn't cost you more. For the price, I'd just find a way to carry a nail and a little piece of glass with me safely. You should be able to buy a little piece of glass from a glass shop so you don't have to carry around a broken piece. Or do what I did and tumble a piece of beer bottle. Here's that link: amzn.to/3CyyZKI

[@gregbickford1341]

very interesting. thank you! great family

[@soul_adventurist]

Thanks for sharing this, it definitely cleared things up for me!

[@MichiganRocks]

You're welcome!

[@justjulee9135]

This was great! Loved seeing your daughter, son-in-law, and grandson! You have a beautiful family! I love knowing I can test rocks in the field now too!

[@MichiganRocks]

Thanks, Julee. I'm glad you found it helpful.

[@silkeeberle8484]

😄 Love the Picture! There's a new Boss in Town! Very interesting and enjoyable segment.

[@MichiganRocks]

He’s the boss alright. He just cries and someone jumps.

[@brianholcomb940]

Thanks for the info! Interesting to hear the difference in the hardness of various minerals and rocks! Helps with tumbling! Thanks for sharing!

[@MichiganRocks]

You're welcome, Brian!

[@wolfe1970]

Cool video, will share with our group as this question is asked alot and you both covered it really well

[@MichiganRocks]

Thanks, I appreciate that.

[@JohnnyTakeAll]

Very informative!

[@RobHostetter]

Nice to see Joseph is wearing the Michigan shirt. Have fun with that baby.

[@MichiganRocks]

They were just here for the weekend, but Joseph got held a lot. It was great to see all of them again.

[@jade-wr9pn]

By far THE greatest thumbnail, hands down 😂😂😂

[@MichiganRocks]

I can't take credit for that one. It was David's idea, I just followed his guidance.

[@jade-wr9pn]

@@MichiganRocks absolutely hilarious 🤣 thank you both for this video. I wasn't even sure how to go about learning this information

[@vesnarandelovic9934]

God bless you and your family 🙏

[@MichiganRocks]

Thanks, Vesna. God bless you too.

[@Absolution55]

Pretty cool video

[@micheleboyd1830]

I love the thumbnail for this video. Lol. Also so interesting learning about the different hardnesses of minerals and rocks. Thanks!

[@MichiganRocks]

The thumbnail was David's idea. We both liked it too.

[@shannonreynolds4423]

Joseph I did see you wave hello and stick out your tongue at us :) You stole the show! Thank you all for this informative video I learned a LOT.

[@MichiganRocks]

He was pretty well behaved for his first appearance on KZbin.

[@lynettepavelich7540]

Joseph is getting so big! Nice presentation, David! Go Chips! I went to school there probably before he was born!🤪🤣

[@MichiganRocks]

Allison and David met at CMU.

[@manisteerocks7092]

I can memorize alotnof stones mohs,..but now I know what it really is and how it works. Very informative and nice demonstration. Thankyou for providing this information. You have a nice family!...ya need a little green and white in there somewhere tho..I'll have to send youba mug.

[@MichiganRocks]

We have some green and white in the house. Those are Alpena's colors!

[@manisteerocks7092]

@@MichiganRocks nice save Rob,nice save..

[@jellythingy]

ty rob

[@Birdlab]

Nice job David. Fire up Chips!

[@silverlover5817]

Beautiful family! Thanks for the video............

[@shel.b.1090]

That was really useful, thank you xx

[@MichiganRocks]

You're welcome!

[@Charlie-lh4xb]

Knew about the Mohs scale but using the different items in your pocket to test hardness is definitely food for thought. Great video👍

[@MichiganRocks]

He thought he had a testing kit comprised of those items with him, but didn’t. It took me less than five minutes to gather up a complete set of testing materials.

[@victoriadawydiuk4172]

Mohs videos like this would great😆

[@MichiganRocks]

I’d say moh are on the way, but I’m not sure what the next geology video will be.

[@cvx2dog549]

Great lesson about the Mohs Scale!

[@rockaholic4388]

Well isn't David just the cutest thing ever!

[@MichiganRocks]

David or Joe? David's the big one, Joe's the little one.

[@MsSandraCGL]

Awesome thank you so much for this lesson, in the hardness and how you can test it.

[@mtonjum]

Thanks for doing this video! So helpful for a new rockhounder 😁

[@captpaul8827]

Nice little video. One thing to watch with a penny is that they are copper-plated zinc these days, so you may not get an accurate reading. You're much better to have a piece of coarse copper wire to use to test hardness which is about 3.5. Also, you have to watch nails as their hardness can vary as well. The best thing to have with you in the field are a set of the hardness picks, although they are a little hard to fit into a pocket....

[@MichiganRocks]

I did look for an older penny, but probably not old enough to be pure copper. I avoided the really new, lightweight pennies because I figured any copper coating on those would be very thin. Those hardness picks are fairly expensive based on my quick research the other day. David suggested that using common household items would get you a close enough estimate for more casual rockhounds and cost nothing. Well, I guess it costs at least one cent.

[@johnbyington3458]

Unakite is one of my favorites too :-)

[@maijaliimatta296]

Go Fire Up Chips!!! Helpful video.

[@Angelogemstonesfossil.72]

Good job...

[@emmikate]

Your daughter marrying a geologist seems exactly right. Beautiful family ❤

[@MichiganRocks]

Yes, I approved of her choice.

[@Smallathe]

Very cool!!!

[@jmsdvs5]

They got kits that are lightweight and transportable now. A good one runs about $100 on Amazon. I picked one up and it works great.

[@MichiganRocks]

Yes, there are kits with little picks in them, but this one was free and is almost as good. Do the kits include a diamond tipped tester?

[@wyomingadventures]

Think I will be making a field kit now. Minus the diamond. Only because I don't have one. 😄 When I was married I had a ruby ring. Gave it to my stepson after his dad passed away.

[@MichiganRocks]

We had a diamond, but we weren't allowed to actually use it.

[@CityRockhounding]

Joseph is so cute! What a cool video, thanks for bring David to share this geology lesson! You always hear about rock hardness, so it's cool to see it.

[@MichiganRocks]

It's about time we did this video. David has been suggesting that we do it for awhile. I'm glad we finally got around to it.

[@CityRockhounding]

@@MichiganRocks so glad you did, it's very useful to help me to identify rocks and minerals!

[@donnalantz7981]

Thanks Rob and David. That was interesting to see. And wow ,Joseph is growing so fast. Pretty soon he will be going on rock hunts with his Grandfather. Thanks for sharing.

[@MichiganRocks]

Won't that be fun when he gets to come along? Allison took him down to the lake and dipped his toes in the water. He wasn't too impressed.

[@donnalantz7981]

It will be the best. I've done it with each of my grandbabies now. I have 3.

[@juli6497]

RESPECT THE MOHS!! :)

[@sergeboivin566]

Your son-in-law is a geologist. Very appropriate :-) !!

[@MichiganRocks]

Yes, that worked out well.

[@mawi1172]

I had an inkling of what mohs was. But I'm glad to see this because I bought some "stones" from that lower end there, that just crumbled when I was wrapping them. Now I know why. Don't buy those. Thanks for the info!!!!! 💕💕💕💕

[@MichiganRocks]

You’re welcome!

[@icatz]

Great tute. I knew these but a refresher is always good. Is obsidian to be same as regular glass? TFS 💖🦅🦅

[@MichiganRocks]

I can't say for sure that obsidian is the same as glass, but it should be at least close. I know it's soft when I tumble it.

[@icatz]

@@MichiganRocks I don't think I've ever seen you tumble obsidian.

[@MichiganRocks]

@@icatz I have never shown a video of my tumbling it, but I have tumbled a fair amount of it. Here are two examples: Mixed obsidian: kzbin.info/www/bejne/mpOse2uebJKEibs Apache tears: kzbin.info/www/bejne/poLUkGeVo5mNhKs

[@icatz]

@@MichiganRocks They polished up beautifully! Thanks.

[@cmennare]

It sounds like a trip to Topaz Mountain, Utah is in order to complete his set.

[@MichiganRocks]

Sure, that seems like the most obvious solution. I might have to go along to supervise, too.

[@letymendez826]

Guapo niño 😘 igualito tu 👍 gracias buenas noches

[@MrAntglas]

I’m a beginner, and have a question. I’m an antique glassware collector, and know that from the early to mid 1800’s, “flint”, or lead, was added to glass batches to make it clearer and brighter. Do you know whether “flint glass”, or leaded glass (what some people would refer to as “crystal”) would be harder than typical soda lime glass, like from a soda bottle, or softer, or pretty much the same?

[@MichiganRocks]

I really have no idea.

[@SustenanceNCovering]

What a copper penny will do is not the same as what a regular penny will do. At some point pennies started to be made from zinc.

[@MichiganRocks]

I think we used an older penny.

[@rockaholic4388]

I should have said, "Wow he's cute, and so its the baby!" Haha

[@mawi1172]

Smart kid! Don't tick off the wife! 🤣🤣🤣🤣🤣🤣. You have some beautiful kids there?! 💕💕💕💕💕

[@yeswing10]

Your Son in Law is a Geologist? You guys must have a lot of interesting conversations.

[@MichiganRocks]

He is. Lucky me!

[@yeswing10]

@@MichiganRocks You are very Blessed for sure. Your Grandson will probably be a chip off the old block, too! He's adorable, by the way!

[@robbybobby6483]

Nice video. Hi David. One question. What is the minimum hardness, a stone has to be, to successfully polish? Is the oxidation that forms on the surface of a rock harder than the rock itself? Love the Michigan rocks family joining in. Rob's baby picture? Still adorable as ever buddy.

[@MichiganRocks]

Petoskey stones are a three on the Mohs scale. I can't imagine something softer than that polishing well, but I don't know for sure. Maybe @DenimHatDave can answer your second question. I have no idea.

[@robbybobby6483]

@@MichiganRocks thanks Robert. Have a good night.

[@DenimHatDave]

I would think that it all depends on the type of stone and the method you use to polish it. I wouldn't doubt that you could hand polish just about anything. For example, alabaster is a form of gypsum with a hardness of 1.5-2 which is regularly used for statues and polished pillars. I cannot speak to polishing it in some sort of tumbler though. As far as oxidation or a weathering rind that forms on the surface of the rock, these are intrinsically softer than the host rock as they are a result of the partial breakdown or chemical alteration of the exposed surface of the rock.

[@MichiganRocks]

@@DenimHatDave Good thing there was a geologist handy to answer that one.

[@baron8463]

Thank you for the great content. This was a very interesting video. Have you considered doing a video where you talk about "color"? I learned this from a psych professor of all things but color is an illusion. If you ask some one what color is a "red" rock? "Red" is not actually a correct answer the correct answer would be that the rock refracts only specific light waves so we are seeing light in the 700 nanometer wave length being bounced off of the rock. Is there more to this when it comes to rocks? Have you already talked about this in one of your other videos? It is interesting to me how much water changes the way light refracts off the rocks, how much does polishing the rocks affect light refraction and or "color"? If you have already gone over all of this I am new to your channel and am more interested in the informative how to content then looking at the all the pretty rocks you have tumbled but will have to watch more of your content to learn more about the different rocks. Another suggestion for a video would be if you bought some of the rock blends like how they sell them on amazon and maybe show us how we should sort them to polish based on outward appearance and characteristics, I am just picking out the pretty rocks, my new method is to see what stones wear away the most on grit 1, and take them out and reserve them for polishing so I do not end up with 1.5 inch rocks that become pebbles. I have also been throwing rough rocks that are smaller in with the polish and pre polish so they stay larger, I have no idea if this is a bad idea, as I am still learning.

[@MichiganRocks]

I'm not an expert on geology or color and certainly not on the two combined, so that video is not something that I will be doing. Mixing rough rocks in with other rocks in the polish stage is not something I would do. I'd be afraid that the rough rocks would scratch up the almost polished rocks. As for mixes of rocks, I just don't buy them. Typically, I buy one type of rock and tumble them separately from other rocks as much as possible. I have bought mixes of rocks from individuals online and I do tumble beach rocks of many different types together. With my vibratory tumbler it doesn't seem to matter that much. I'm currently doing a mixed batch of beach rocks in a rotary tumbler where it may make more of a difference. I'm going to find out.

[@baron8463]

@@MichiganRocks With the Nat Geo machine I am using the rough rocks have not impacted the quality of polishing because none of the grit I have will polish the rocks, as you know from your on personal experience with the machine, the tumbler and barrel are pretty good but the polish grit not so much. I wish I had learned a little bit more about rock tumbling before I bought all of the stuff on amazon. The final polish does not really do much and even the 1200 aluminum grit I purchased is apparently just a pre polish from your comment on one of my other comments. I have also already purchased about 10 pounds of mixed rocks, So I will attempt my own sorting video for my channel which has 0 rock content as of now. I will be sure to use the links you shared with me to buy my next batch of stuff!!! I think that it is such an amazing hobby because of all of the variables that you can change and experiment with to get different results. I have learned a bunch of stuff from your content and appreciate your time and know how. Thanks again

[@jamesdemski5231]

Once again awsome vid .. Penny's have changed the recipe due to scrap metal prices .. are Penny's now a days even copper.. or that penny in the vid is copper Cruze it's made b 4 1990 or when ever they changed its recipe? What year penny does he got?

[@MichiganRocks]

We used an older penny, but not a pure copper one. The one we used was zinc with a copper coating. Probably a better thing to use would have been a piece of copper electrical wire.

[@jamesdemski5231]

@@MichiganRocks thanks good thinking got that for sure laying arround here.. thanks again from Detroit love the content

[@debivort]

Next video on streak tests?

[@MichiganRocks]

That’s a good idea. Maybe we’ll do that.

[@TinaHyde]

Yeah, I’m gonna need more Joesph content next time. His dad’s a smart guy and all, but enough with the rock stuff already - I’m here for the cute grandkid now… 🥰

[@MichiganRocks]

I can't promise to put him in every video since he lives four hours away, but I'll try to get him in once in awhile.

[@TinaHyde]

@@MichiganRocks Four hours?? 😩 We’re gonna need them to move closer…

[@nighredemption]

Just out of curiosity, is it possible to polish raw uncut rubies?

[@MichiganRocks]

I'm sure it is, but I don't have any uncut rubies to experiment with.

[@jeremyadams451]

Where do you buy your grit from and/or what brand do you use?

[@MichiganRocks]

I get my grit from the Rock Shed. There's a link in the description of this video and I also have it in my Amazon storefront.

[@Banjoliope]

Shouldn’t we try to find an older fully copper penny, as opposed to the newer ones that are only copper plated?

[@MichiganRocks]

Yes, an old copper one would be better. I didn't find one that old, but I did grab one that's older than the really new ones. Someone else suggested that a piece of copper electrical wire would be even better.

[@Banjoliope]

@@MichiganRocks Thanks for the quick response! 😃

[@johnbaenen5386]

Some tongue twisters in there.

[@obieobrien5883]

Would you please show David the pictures of the rock I sent? Thank you

[@MichiganRocks]

No, I don’t want to start taking up his time identifying rocks for other people. He works full time and is now raising a son. Your best bet is to find a rock identification group on the Internet. Facebook has some.

[@obieobrien5883]

@@MichiganRocks , I understand, thank you.

[@missmaria165]

Hi Baby! 👋 😇💙

[@sabeidaarias6981]

😍

[@deniseview4253]

Cute grandbaby

[@michaelwilner4756]

Judging by the shirts, Michigan has some kind of higher learning institution no? 😊

[@MichiganRocks]

Yes, that's true. The _highest_ of the higher learning institutions is The University of Michigan.

[@captpaul8827]

@@MichiganRocks I might disagree..... ;-)

[@MichiganRocks]

@@captpaul8827 If you're going to rock school, then Tech is the way to go. No argument there. Although my son in law might disagree.

[@katiedid713926]

Absolutely handsome Joseph

[@minecraftguy567]

The husband gets shot in the end

[@mawi1172]

The one thumb down must be a Minnesotan. 🤣🤣🤣🤣

[@MichiganRocks]

Who, David? He’s from Michigan. He was even wearing a CMU shirt.

[@markreetz1001]

Whew!! No test! Thank Goodness!! So your daughter brought home a geologist for Dad, eh? She'll be complaining he spends more time with you than with her! lol!

[@MichiganRocks]

Lucky me!