Very awesome Video about specific gravity test for gem and mineral like rough raw diamonds. Very very useful and accurate Method. Yes! Simply but efficient and effective. Thank you very much for helping us how to do demonstration home test.❤❤❤❤❤❤❤❤❤❤❤🎉
Very helpful! thank you so much! Right to the point. I hate when people draw things out in the beginning and I have to skip around to find the pertinent information scattered within all the nonsense. No nonsense here! Thank you! :)
I would only say that it is necessary to suspend the paper clip in the container of water before zero'ing the scale for more accuracy. Otherwise, you're including the weight of the paper clip in the weight of the second measurement when it shouldn't be. For heavier minerals, it shouldn't affect the results too greatly doing it this way, but for far lighter minerals, the outcome will differ quite a bit
Raj Siewrattan No don't touch the paperclip to the container, but rather make a visible mark on the paperclip and insert without stone up to that mark and then tare. That will then account for the clip for even more precise accuracy. Good point though.
More accurately, what you include is the weight of the water displaced by the paper clip itself. So for instance using a thinner cable or thread will make the reading more accurate.
Here's the explanation of the physics behind this test as I understand it. The specific gravity by definition is the ratio between the weight of an object and the weight of the water of the same volume as the object. The weight of the object we measure directly using the scale. Now all is left to prove is that when we suspend the object in the water, we are in fact measuring the weight of the water of the same volume as the object. When the object is suspended in water, the following forces act on it. There is a gravity force acting in the down direction (let's call it G_obj). There is buoyancy force acting in the up direction (much like it would for a ship at sea) - let's call it B. And there is the tension force of the cable holding the object - let's call it T. Since the object stays in place these forces balance. Therefore T = G_obj - B. What the scale measures, is the gravity force (expressed as weight) acting on the entire setup minus the tension force T. That's because we are essentially supporting part of the setup and the rest is supported by the scale. The gravity force for the entire setup is G_obj + G_watercup. So the scale will measure G_obj + G_watercup - T = G_obj + G_watercup - (G_obj - B) = G_watercup + B. But we actually use scale's tare to subtract G_watercup. So we get a reading of exactly B. But the buoyancy force is actually equal to the weight of the displaced water - which is what we wanted. The important thing to consider for this experiment is to use reasonably pure water. Impure water will have a different density which will result in a different buoyancy force. Similarly, it's important for the water not to contain air bubbles as this will make it less dense, again affecting buoyancy.
I think your Physics is sound. But please explain it, if you would, when the weighing is done through the Tension force. I'd like to check if my asumptions are correct.
Try using braided fishing line rather than the paper clip. The lower displaced volume of the line will result in less calculated error, and will get you a more accurate S. G.
Your video is very clear and easy to follow and the test itself is interesting ; using Archimedes Law( I think) to tell whether it is Topaz or Quartz. I enjoyed this.
Just curious as to what you say to those who say the formula that you divide by should be the difference between the two weights and not just the weight in water. The outcomes are very different. Thanks.
I don't think so, the scale measures the weight of the displaced water. This can be derived by just analysing forces acting on the submerged object. If one wants to see that this is true more directly, the easiest way is to submerge a sphere of a known dimension. The volume of the sphere can be computed analytically using the formula 4/3 * Pi * r^3. Then one can compare this result with the scale's reading. My results were within 1% accuracy, so pretty nice.
I suspect if you weigh the stone in water by let say a spring scale "from above", the reading would be 7.8. Then, the specific gravity would be 12.6/12.6-7.8
I have been googling and thinking about the Science behind it for the better half of the day 🤣. I think I got it. But just need somebody to confirm. Both calculations (his video and mine) are correct, two sides of the same coin. Just depend on which force you are measuring (I think🤣)
hahaha easy peasy, specific gravity. I knew it was easy. thanks for demonstrating this way. scale all i need and ca see quartz, the thing clear, quartzy looking, couldn't be a huge, Washington, a few rare? Diamonds?! sure. do the test, nah hold the lottery ticket, check the numbers later, it's still a diamond maybe, now. :)
to me this looks like some kind of black magic. how can the scale register the weight of the object if its weight is suspended by something outside the area of the scale? Does the weight of the paperclip interfere with the reading?
![The Weight of Truth [Specific Gravity]](/img/n.gif)
Nice video, I believe the paper clip (mark it how far for when weighing with stone) should of been tared out with the water and container
Very awesome Video about specific gravity test for gem and mineral like rough raw diamonds. Very very useful and accurate Method. Yes! Simply but efficient and effective. Thank you very much for helping us how to do demonstration home test.❤❤❤❤❤❤❤❤❤❤❤🎉
Very helpful! thank you so much! Right to the point. I hate when people draw things out in the beginning and I have to skip around to find the pertinent information scattered within all the nonsense.
No nonsense here! Thank you!
:)
Nice and easy way of making people understand. good job.
Thank you sir! It's so clearly to understand 👏
You did not tare the paper clip and that is big error, you should tare scale with the paper clip this would give you more acurate result
I would only say that it is necessary to suspend the paper clip in the container of water before zero'ing the scale for more accuracy. Otherwise, you're including the weight of the paper clip in the weight of the second measurement when it shouldn't be. For heavier minerals, it shouldn't affect the results too greatly doing it this way, but for far lighter minerals, the outcome will differ quite a bit
Raj Siewrattan No don't touch the paperclip to the container, but rather make a visible mark on the paperclip and insert without stone up to that mark and then tare. That will then account for the clip for even more precise accuracy. Good point though.
istvan meissler agreed sir. Perhaps my wedding was a little of beat but that is precisely what I was meaning. I do appreciate the feedback back though
More accurately, what you include is the weight of the water displaced by the paper clip itself. So for instance using a thinner cable or thread will make the reading more accurate.
I used this exact method to test for the specific gravity of my cat!
Simple, clear and effective demo
Very nice, thanks for posting.
Here's the explanation of the physics behind this test as I understand it.
The specific gravity by definition is the ratio between the weight of an object and the weight of the water of the same volume as the object. The weight of the object we measure directly using the scale. Now all is left to prove is that when we suspend the object in the water, we are in fact measuring the weight of the water of the same volume as the object.
When the object is suspended in water, the following forces act on it. There is a gravity force acting in the down direction (let's call it G_obj). There is buoyancy force acting in the up direction (much like it would for a ship at sea) - let's call it B. And there is the tension force of the cable holding the object - let's call it T. Since the object stays in place these forces balance. Therefore T = G_obj - B.
What the scale measures, is the gravity force (expressed as weight) acting on the entire setup minus the tension force T. That's because we are essentially supporting part of the setup and the rest is supported by the scale. The gravity force for the entire setup is G_obj + G_watercup. So the scale will measure G_obj + G_watercup - T = G_obj + G_watercup - (G_obj - B) = G_watercup + B. But we actually use scale's tare to subtract G_watercup. So we get a reading of exactly B. But the buoyancy force is actually equal to the weight of the displaced water - which is what we wanted.
The important thing to consider for this experiment is to use reasonably pure water. Impure water will have a different density which will result in a different buoyancy force. Similarly, it's important for the water not to contain air bubbles as this will make it less dense, again affecting buoyancy.
I think your Physics is sound. But please explain it, if you would, when the weighing is done through the Tension force. I'd like to check if my asumptions are correct.
Very helpful. Thanks for taking the time to make this video.
Thanks for the video it was helpful
Its very awful thank you for sharing your thoughts efficient ideas in identifying rough Minerals.🎉🎉🎉❤❤❤
Try using braided fishing line rather than the paper clip.
The lower displaced volume of the line will result in less calculated error, and will get you a more accurate S. G.
Thank you !
OK what cool mineral did you find in the desert now?
@@maxsands3861 Looks like it’s Stolzite for sure. It has a fairly high SG and the crystal structure is an exact match.
Thank you that was beyond helpful!
You're eyes are so contagious
U bery smot man. Tanku
Very useful to us sir thank you very much
Your video is very clear and easy to follow and the test itself is interesting ; using Archimedes Law( I think) to tell whether it is Topaz or Quartz. I enjoyed this.
Thank you so much
Geology Class Moment!
Thank you
Sir correct method is this
12.6/12.6-4.8 results for this is called specific gravity.
Hello.thank you for sharing this clip .i have a question , dose this method work for a small rough or gem? .i mean around one or 2 carats ?thanks
Good thank sir. And should be clearly back ground.
Just curious as to what you say to those who say the formula that you divide by should be the difference between the two weights and not just the weight in water. The outcomes are very different. Thanks.
Sir it would be 12.6/12.6-4.8 isn't it? Please explain
Same question
BHARAT RATNA SINDHU
Yes, I think you are correct, Bharat--other YT vids show your formula as the correct calculation.
I don't think so, the scale measures the weight of the displaced water. This can be derived by just analysing forces acting on the submerged object.
If one wants to see that this is true more directly, the easiest way is to submerge a sphere of a known dimension. The volume of the sphere can be computed analytically using the formula 4/3 * Pi * r^3. Then one can compare this result with the scale's reading. My results were within 1% accuracy, so pretty nice.
I suspect if you weigh the stone in water by let say a spring scale "from above", the reading would be 7.8. Then, the specific gravity would be 12.6/12.6-7.8
I have been googling and thinking about the Science behind it for the better half of the day 🤣. I think I got it. But just need somebody to confirm. Both calculations (his video and mine) are correct, two sides of the same coin. Just depend on which force you are measuring (I think🤣)
hahaha easy peasy, specific gravity. I knew it was easy. thanks for demonstrating this way. scale all i need and ca see quartz, the thing clear, quartzy looking, couldn't be a huge, Washington, a few rare? Diamonds?! sure. do the test, nah hold the lottery ticket, check the numbers later, it's still a diamond maybe, now. :)
to me this looks like some kind of black magic. how can the scale register the weight of the object if its weight is suspended by something outside the area of the scale? Does the weight of the paperclip interfere with the reading?
hey i have a very beautiful rock/gem/quartz? could someone help me ID'ing it? found it in the hunter region NSW Australia. Cheers
20 pound nugget! Gold, or Opalized Gold :O Nugget! Opal Aussie Mines. ;) finds...
But how to test the mineral in a ring? Plz don’t tell me by color or hardness test
Are you using grams,carats, or ?
thnnxxx man
Was hoping you could explain how this works my mind is very confused.
The scale measures the weight of the water displaced by the object. I wrote a comment with more detail.
For maximum accuracy please see my comment to Raj's post below.
Would this work for a rock that may have multiple minerals.
This method assumes that the density of the object is uniform. For two material object you would get the average density of the entire object.