 Very closely related to color is the streak and I'm going to pick up my streak plate here set it down next to my samples and this is a unglazed porcelain plate so it's just a little bit rough and when I pick up a particular sample and run them over this what I get is just a little bit of a powdered of the sample and three different things can happen in some cases the mineral is so hard that it doesn't actually leave a streak on the porcelain plate and therefore we won't see any streak color at all in other cases the streak color of that powdered mineral might actually be white making it kind of difficult to see now on the lab you could take your finger and run it over the plate and be able to tell the difference because if it's that white streak you'll get some of that white powder on your finger where it's a little easier to see than just on the plate and then most samples will actually leave a definite color so let's go through our particular samples and I'm going to start with the calcite I'm going to run this up and down you hear the scratching and I'm going to do it a lot so we have more to look at when I pick up the magnifying glass I see something there although it's hard to see exactly what it is it's very very light colored so I would call this one white now in the real lab you'd have to either get a clean plate or wash the plate in between these samples in this case the simulations is going to kind of keep turning it over to a fresh side here's our mica and this is a mineral that definitely has a color and you should write down that color in your lab manual as the streak color for mica then quartz again getting a new plate don't see a definite color and don't actually see anything at all so quartz is an example of one that doesn't have a streak color these last four I'm gonna do them but I won't comment as much you need to write down your observations in your lab manual sulfur this is our magnetite our pyrite and then our unknown sample write down your observations for all of these things in the section for the streak