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 !
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.
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.
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!
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.
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.
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.
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
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.
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!
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....
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.
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.
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.
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.
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.
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.
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!!!!! 💕💕💕💕
@@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: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-dbIJ8h7-QSY.html Apache tears: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-pQq_4_n4ZNI.html
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?
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?
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.
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.
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.
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.
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.
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.
@@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
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… 🥰
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.
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.
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!
