I got this as I often have use for a mortar and pestle, whether it be for chemistry or for cooking (spices). I included a picture of my other mortar and pestle of similar size. It is made of ceramic, and as you can see, there is discoloration and staining in it. I promise that I have gone to great lengths to scour it clean, including using scouring powder. Not to put too fine a point on it, it's obvious contamination that I can never remove, unless I want to go to great lengths, such as mixing up a weak sulfuric acid solution to clean it every time I use it. Despite actually owning a supply of lab-grade sulfuric acid, it's still something I'd rather avoid if I can at all help it.This new Lab4US agate mortar and pestle is the answer to the contamination question. Being VERY hard, and VERY smooth (it's actually kind of...calming...to touch, being so smooth and cool to the touch) I don't have to worry about bits of sulfur or iron oxide or some other such thing being ground into the surface of it. It's as hard as a hard tool steel, and since I'm not grinding up...well, diamonds or anything like that...it should last forever.Like any decent chemist, I keep a supply of raw elemental sulfur in my chemical cupboard. If you've ever had the pleasure of grinding sulfur, you know 2 things. 1, it smells absolutely wonderful. 2, it's kind of "sticky" when you grind it, and can be time consuming to grind because of it.I put a small portion of elemental sulfur pellets in this delightful little (perfectly made) mortar, and proceeded to grind it up with the pestle. It was actually much quicker and easier with this smooth bottom mortar than my old set. I would say my "grind time" was probably cut about 25% or more using this vs my old one. It went VERY quick and easy. Cleanup? I would have had to scrub sulfur out of my old mortar with scouring powder. I scraped my sulfur out with a plastic scraper (it came out VERY easily, practically "non-stick") and wiped it clean with a dry paper towel.With a dry paper towel, I said. I didn't wash it for these photos or anything fishy. This is a plain, dry, paper towel wipe out after grinding sulfur. Anyone that's ever done this procedure with a junk mortar and pestle should see these photos and smile, and click "add to cart". Because it's a huge time saver to have a tool such as this. Is it $70 for a little 60mm mortar and pestle? Yeah. It is a bit pricey. But boy oh boy if you work with materials such as this (even plain old kitchen spices, cooks will LOVE this), you will appreciate spending a few coins on a quality tool such as this. It is well worth the cost. And the fit and finish is legendary. I may display it on a shelf when I'm not using it.So if you're using a kind of budget mortar and pestle as I've been using for quite some time (I think I paid $12 bucks for a set of 3, lol), and you have concerns about contamination between grinds, and are looking at the agate versions and going "Wow!" at the cost, understand that you're getting a much better tool than some cheap fired clay ceramic mortar and pestle. You will be spending good money here. As someone that actually uses a mortar and pestle fairly often, this is now my "go-to". And I'm now looking at getting a bigger one! Because this is just amazing.If I had to wish at it, and say "Make it EVER BETTER!", I'd say I wish it came with some kind of storage case or something. It's nice enough that I don't want it just rattling around in some cupboard but would rather have it in a nice case. But, it's just a "wish item", and doesn't detract from what is a wonderful tool.In all, I have no real complaints about this at all. It's beautifully crafted and saves me real time and effort vs my old set. If you haven't yet invested in an agate mortar and pestle, I personally recommend them as being well worth the expense. 5 stars.