 Okay, so we're going to take a look at some grains and the different types of grains. What I have on the table here in the dish are grains that came from Bodega Bay area. I had them drying out on the back patio here and the raccoons kind of homogenized them. So there's little bits of debris. So this is, for example, a little bit of an acorn from my oak tree. So that's not an original component, but it's a good example of an organic biological grain. Get rid of that one. Not sure what this one is. That might be some of the same thing. We have other biological grains. So here is a white colored shell and here's a pink colored one. Here's one that you can see some of the shell pattern on. This one might be a little bit of a purple shell from a mussel. I would need to use my hand lens to look at that for sure. So we have some skeletal grains and one of the things to note is that they don't retain the original geometry of the shells. They're broken and they're fairly rounded and that's from the transport processes. Generally when grains get transported they collide against each other which breaks them and the little angular bits are broken off more easily. I think that there are a couple of angular grains in here. So for example, here's one right here. It's white on a white plate so it doesn't show up too well. It is light colored and opaque and has a pretty square outline. And I think that's probably a feldspar mineral. There are granitic rocks around Horseshoe Cove at Bodega that are weathering right there and producing some of those grains. We also have chunks of the rock itself. So for example, this grain right here has both white and black although now I'm wondering if it's a shell. Again, I might need to use my hand lens. Here's an example of a lithic clast. It's got the multiple colors, multiple minerals. So this little grain right here is actually a rock so we would call that a lithic clast. Oh yeah, there are quite a few of those now that I have my eye into it. Here's a little orange grain that looks like it's a fine grained metamorphic rock. There are a lot of those in there. So most of these grains are rounded. The few that are angular probably haven't been on the beach very much. The beach rolls the grains back and forth. They collide against each other and that causes the rounding in the grains. The same is true for grains that are deposited in a river. Another thing you'll notice is that there's really a wide range in the size of the grains. And so we use a grain size chart like the one here that has measurements and microns for the grain sizes. A fee classification, which is sort of a binning that we use to say how well the grains are sorted or how uniform the sizes are. And then it has this nice scale here with representations of those size grains. So if you put the grain size chart right up against some of the grains or some of the grains on it, we have some that are this course's size, which is upper, very coarse. We even have some that are larger than that, like these grains here. And some of these would be granules or up to pebble size. We also have these fine sand grains. See if I can get some of them to separate out here. And those sort of come down into probably mostly the medium sand, some fine sand. And then it gets really hard to see this, I should say, fine sand upper category versus fine sand lower. Some of it's pretty fine in there. And obviously once it gets too fine, you can't really see it with your plain eye, you need a hand lens, or sometimes you can also feel the difference. So one of the things that happens is when the large grains break and the sharp edges break off as they round, they produce finer and finer grains. So the process of sediment transport goes from having coarse grains, coarser grains, that tend to be angular, and as they're transported, they become more rounded and finer grained in general. There are some rocks, like if you're breaking down a rock that originally has fine grains and fine crystals, that's the size that it'll produce. It'll produce lithic fragments that can be larger and then the finer grains.