okay we going talk about minerals today and really how they breaks cleavage of fracture can be quite tricky uh the video is not the greatest way to do this is best uh with real hand samples but this is what we have so uh we're looking at broken pieces of minerals that have to be broken and uh it's either going to break with cleavage or fracture cleavage what you're looking for is if the mineral breaks with any flat sides or angles or geometric shapes then it has cleavage uh fra if it's R the surface has random breakage or bumpy surfaces and no flat sides or angle so um let's look at some examples of it now okay here we go let's do a cleavage ref fracture let's look at this piece right here fracture what's up next and cleavage ref fracture any flat size order patterns cleavage that one is cleavage it breaks this way this here now this is a very good example of cleavage you see cleavage on all the sides very clean angles so very obvious cleavage but not all cleavage is that clear or noticeable okay I have this one here okay let's do this now this is cleavage see oh you see the see how this light shines off it right there and see the angles there so uh that right there you really can see that's cleavage although like on this side a lot of students often will not see it here uh as long as there's any sides that are flat in order even though the other sides maybe you don't really see it that still has cleavage it does not need to be perfect like this all the way around okay that is a common mistake this one here that is fracture fracture what else do I have here this is fracture so it's surface very bumpy sometimes the problem is that it it has a glassy look to it so people confuse it for Cleavage but this is fracture what else we got how about this it's good to hold it into the light to see how the light reflects off it this is cleavage see hope you see all the little steps and angles in there they're kind of small but uh cavage this may be a little more challenging cleavage ref fracture actually it's a little hard to see it's hard seeing a light but you can see the flat wave reflects the light right there on that side you you see it there a bit you see it kind of right there my lighting is not the best that is cleavage though if you're having trouble with that on the video that's very understandable um you see that right there it reflects the light and again I have a very harsh light here so this that is cleavage it breaks flat on this side here and you can see it here or hopefully you can see it there you see this angle right here that it makes so that is cleavage okay cleavage ref fracture that is fracture okay today we're going to learn how to scratch a glass plate with a mineral this is a hardness test for minerals okay you want a glass plate like this here I have some minerals so what you want to do is this you want to get your glass plate you want to hold it firmly I'm going to start with this one right here calc and you're going to drag this on the glass plate key thing here here eyes closed okay very rarely in school do you need to keep your eyes closed when doing something the teacher says this is one eyes closed because it's about the feel of it you're going to feel it dig into the glass or you'll feel it Glide across the glass so watch me here I go I keep eyes closed want to press kind of hard not too hard to break the glass press hard and do one good pull towards you okay now this is all about feel okay I could feel this this is T I feel it Glide across the glass you can feel it dig in or not dig in let's try something else let's try another one I will try this is a piece of gypsum I'm going to try this again eyes closed pull it on the glass oh I really feel that Glide across it does not dig in at all digging in or dragging on the glass is scratching it uh sometimes it's obvious and sometimes it's a little hard to tell I'm going to try quartz here going to hold it firmly like this you want you want to press hard but not too hard okay some people do it like they go like this they go oh like that this that's not going to do it you need to press harder than that so hold it down grab it firmly uh and then press eyes closed and I really feel that dig in you can even hear it dig in uh this is clearly scratches the glass and again you feel it like dig into the glass drag on the glass so that's pretty clear there's some other minerals that uh are a little more difficult to tell and sometimes you know you got to like here I'm going to flip this over you have to drag it on here I can't really tell if it dig digs in or not you know uh flip it over try another side try another edge here is it digging into the glass uh and you can't always tell by looking at it sometimes it rubs off so try a bunch of different sides uh that's key to it remember eyes closed for