We just mesh well.

We are always happy to answer customers' questions about these raw materials; we know that chemical knowledge in the ceramic realm is daunting in its scope, and there is a LOT of information out there. Because of this, we get a lot of phone calls! Within all of those phone calls, though, there are a handful of questions that keep popping up, and this blog is a great place to begin addressing our most frequent inquiries. Have an inquiry yourself? Leave a comment, and I'll be happy to answer!

Inches. Centimeters. Microns. 

...mesh size?...

While all of these terms are units of measure that can be particularly useful to the ceramic enthusiast, only one -- mesh size -- comes across as somewhat ambiguous, as experience in raw materials consultation has taught us. Here, I explain what mesh size is -- and, more importantly, how you can start to consider it when you have option for purchasing the same material in different mesh sizes for your clay and glaze fabrication.

Mesh size is sort of like the thread count of the pottery world -- and beyond. This is a useful macro-level measurement in the fields of geology, soil science, archaeology, and more. That's right -- this is a standardized unit of measure that is utilized in many earth-science based fields, so you can push your glasses a little further up your nose and give a nod to your newfound earth-y science-y cohorts.

Taking a cue from one of those sciences, let's look at the classic geological soil size chart. This chart explains the difference in relative sizes between three categorizations of sediments -- sand, silt, and clay. Sand is the largest particle out of the three; silt is the middle child; and finally, tiny, little clay particles are the smallest.

So the graphic above lays out the technical size range of each of these important particles -- but if you're out in 'the real world' -- and by 'real world', I simply mean a world in which you don't have immediate access to, say, a microscope -- how can you tell what size particles you are dealing with? How do you separate sand from silt from clay if you are doing a project that involves mining and levigating your own clay? On my end, I've worked extensively as a field archaeologist, and I've often been called upon to do trenchside soil analysis, which means I have pretty basic equipment to work with to determine the relative particle-size makeup of any given deposit.

So what do I use?

MESHES.

Oh man, do I love shaking some dirt in a stack of mesh screens. Basically, in the graphic above, uppermost mesh size is your largest mesh size, with the largest-sized openings through which particles can pass. Anything larger than that stays in the tray, and when you look over at it, you know roughly how much dirt didn't pass through the 10-mesh -- meaning its particle size is larger than that. This continues down the line, with increasingly finer particles distributing through increasingly finer mesh sizes. The thing is, though, as scale of measure is not entirely intuitive. For instance, what does '10 mesh' ACTUALLY mean, size-wise, for the newbie?

Perhaps if you've purchased raw materials before, you've noticed certain chemicals come with a number attached -- say, 'Silica 325' or 'SMS 200' (SMS is the brand name for Stone Mountain Silica). Those end-numbers generally refer to a mesh size -- and this is important -- the larger the number, the smaller the particle! So Silica 325 has passed through a 325-mesh screen, which consists of particles that are smaller than 0.044 mm, while a (larger-sized) 200-mesh screen passes particles smaller than 0.074 mm. Those numbers are so tiny that both of these types of silica appear exactly the same if you place them side-by-side with the naked eye; both will present as extremely fine white powder. However, although these differences are literally quite slight in most applications, understanding relative mesh sizes, and how different sizes of materials might affect your clays and glazes differently is an important corner of the physicality of ceramics. 

And with that, I'm really starting to veer into ranty, too-technical territory -- so, to sum it all up, I've compiled a neat little list of mesh size references that you are likely to come across while shopping for raw ceramic materials, as well as the typical application of each mesh size.

20 mesh -- These larger-sized particles -- just under 1 mm -- are considered coarse for the ceramics world. You will likely see this size in association with coarse grogs. This mesh size is too large to be attached to any fine powdered pulverized materials. To give you an idea as to what 20-mesh feels like, playground sand is a pretty good visual. This is generally the roughest stuff you can (commercially) add to your claybody, so if you are new to clay formulation and want something smooth for the wheel, I'd recommend a smaller mesh size (but larger mesh-size number). 20-mesh grog is a great additive for large-scale sculptural works -- it will give your claybody a great, rough skeleton, and often contributes to a beautiful surface texture, as well, when used in large enough quantities.

35 (or 40) mesh -- Still on the 'larger' size as far as ceramic-industry particles are concerned, 35-mesh is often seen in association with medium grog. If you are looking for a gritty (but not TOO gritty) additive for your throwing claybody -- one that isn't so rough that it will chop up your hands -- I'd recommend this. This mesh size, as a grog, will also serve sculptural claybodies well.

80 mesh -- Perhaps you've seen this as a suggested mesh size to use when mixing glazes. 'Sieve twice through 80-mesh (or higher)" is typically seen on dry glaze mixes. That size is usually sufficient for breaking down the clumped-together materials in a glaze, but for recipes containing commercial colorants such as Mason Stains, I usually recommend using a smaller sieve, such as a 100-mesh. When I worked as a studio tech, my 80-mesh test sieve was one of my go-to items. It fits right in the top of a deli container and is the perfect size for small test batches of, say, 200 grams.

200 mesh -- This is where clay additives and glaze additives start to overlap, in general. This is a mesh size that results in a fine powder -- baby-powder consistency, really -- 

200-mesh is also the standard mesh size of fine grog. I mention this because people frequently order fine grog -- which pretty much looks and feels like a very fine powder -- when they actually want the toothier, larger medium grog. Fine grog is just that -- fiiiiiiiiine. And, for certain applications, it still largely works the same way. This pulverized refractory material lends strength and durability to your pieces, but given its powdered form, it's not the best choice for, say, large-scaled sculpture or wheelthrowing. It does add great strength to fine claybodies without detracting from detailed-working qualities, though. 

325 mesh -- This is the smallest/highest mesh size that you will see on ceramic products, for the most part. There are some 400-mesh products on the market, but 325 -- that's pret-ty small. 

So, if mesh sizes like '200' and '325' are so small -- small enough that by handling or looking at them, people cannot tell the difference -- what's the main difference between the two? How, specifically, can we observe them actually behaving differently as glaze or clay additives? There are a few different thoughts on this. In terms of adding, say, silica to a claybody, having a variety of different particle sizes in the super-tiny range can actually cut back a bit on shrinkage. So, if you're working with a high-shrinkage claybody -- say, a porcelain you are mixing yourself -- and you're having trouble with glaze fit or any other number of issues that can arise from a clay moving and shrinking a lot, sometimes mixing in a silica content of varied grain size -- such as 200 and 325-mesh powders -- can help that a bit. As far as glaze formulation is concerned, smaller particles stay in suspension longer, so most glaze-mixers prefer Siilica 325 over the (slightly) larger, (slightly) heavier SMS 200. 

These explanations, of course, are the greatly-abbreviated versions, and the staff at The Ceramic Shop always encourages further research (for ourselves, as well!). Hopefully this will provide you with a good starting point for understanding the correlation between mesh size, particle size, and practical application. Questions? Ask away in comments!

In the Philadelphia area (and beyond!), The Ceramic Shop has really filled a niche of supplying raw ceramic materials to studio potters, university classrooms, and independent artists alike. We pretty much sell it all, in dry form, by the pound. So whether you are just learning how to make and test your own glazes, or you're a seasoned pro, we have a VERY stocked warehouse that has pretty much everything you need.

Hello, summer!

Or, how to maintain your studio practice when you no longer have a studio... 

 Goths on the beach. Yay summer!

At The Ceramic Shop, we deal with schools of all kinds -- from elementary art programs to university ceramic departments, we spend much of the academic year servicing these programs in Philadelphia and beyond. When school ends for the year, though -- no matter if it's college or pre-K -- ceramic work doesn't have to stop, even if you no longer have access to your school's art studios. We often speak with students who aren't always sure about how to proceed with continuing to make work without a kiln, or a large array of glazes, or that ever-abundant studio clay.  Granted, that's one aspect of ceramics that can, indeed, be difficult -- your work and progress can be so access-dependent. Well, many of us on The Ceramic Shop staff have been there, and as such, we have plenty of suggestions for keeping your practice alive during those moths when school is out.

In the first place, keep an open mind here -- you may have to get creative! Luckily, if you're embedded in the arts, you probably ARE creative, so that part won't be hard. Also, be willing to alter or expand your practice to materials/spaces/scales/etc. Below, I've posted a quick guide to products, home-studio suggestions, and resources (focused on Philly, because that's where we're located) for the ceramic artist on summer sabbatical. 

1. Consider using materials that do NOT need to be fired.

This Marblex self-hardening clay is just one of several self-hardening clays that we offer -- in general, these are air-drying clays with a decent working time, and once they SRE dried, you can paint or sand them. As its name suggests, Marblex is fairly hard, which makes it a durable choice for the artist who may be used to working with hearty fired clays. This clay in particular is nice for jewelry, beads, smaller sculptural works, and other projects, and it comes in a 2-lb. block. Check out our other self-hardening clays here. (Look for products labeled 'self-hardening'.)

Depending on the kind of work you typically make, you may hit some limitations here -- if functional wares are your thing, self-hardening clays really aren't the best materials. Also, if you work on a larger scale and are accustomed to purchasing clay in the standard 25- or 50-lb. bag or box, self-hardening agenst are sold in smaller amounts -- usually 2-5 lbs. However, if your goal is to keep your hands busy during the summer months, it's a decent solution.

2. Catch up on your mold-making.

This, of course, only really applies if you use molds in your work, or plan to use molds, but the summertime is a wonderful time to build up your mold library. Even if you have a small space in which to work, you will be able to make some small sprig molds, which can be used to apply ceramic decorations to pottery once you re-gain access to a studio. We actually carry several already-made sprig molds, just to give you an idea of what they look like:

The mold pictured here is by Creative Paradise -- check out their other molds here.

Mold-making supplies can be reasonable affordable, depending on the type of mold you'd like to make; a spring mold like the one pictures above requires a fairly minimal amount of materials, though. First, you need something you want to cast -- I went through a big kick a few years ago where I made spring molds out of all of my old pencil toppers from the '80's, and now those creepy little plastic figures are committed to clay, permanently. Next, you need some No. 1 Pottery Plaster. This is a very fine-grained plaster that we sell by the pound or the full bag, and it's great for capturing tiny details on small (or large!) objects.  You will also need a clay that can work as a bed or a base for your mold. If you have any clay laying around -- say, reclaim-level stuff, as the mold-making process may leave plaster chunks in your clay, making it unusable -- you can use that. You can also use plasticine, which also serves as a sealant for when you pour your plaster into the mold. Hey, we sell that too! I like this stuff.

You will also need something to pour your mold into -- for smaller projects, a tiny Tupperware-style container is usually fine. As far as further directions for mold-making are concerned, that's a whole 'nother can of worms -- and there are, of course, several resources available online. There's a great quick video tutorial from Ceramic Arts Daily -- you may have to register (for free) for the website to view, but it's worth it. Check it out here.

3. Re-fill your brain bank

Making good ceramic work isn't just about doing, of course -- it's also about reading, looking, and learning. Being 'forced' out of a studio for the summer can be a great opportunity to use a different part of your brain moreso than you might when your hands are constantly in clay. Have you been particularly resistant to, say, learning about glaze chemistry? It might be easy to brush that off when you have access to a studio -- after all, you have to take advantage of that time, right?!? No studio means no excuses! Be hard on yourself in the nicest possible way. And, hey, it's summer after all, which means that in many parts of the world it is AWESOME outside. Catch up on your reading in the great outdoors! 

At The Ceramic Shop, we stay stocked with ceramics-focused books covering a wide variety of topics -- from the technical to the aesthetic, beef up your clay library here.

4. Temporarily join a new art space

It can be really easy to get super comfortable in your school-based studio set-up, but one really wonderful thing about the ceramics community is this: No matter where you hang your clay-encrusted hat, chances are there will be like-minded people who are also just as interested in 

Resources for this suggestion vary quite widely from region to region, but here in Philadelphia, for example, I can lay out what a temporary studio join might look like. One of the most awesome resources that we have in town here is The Clay Studio. This is a ceramics education-based nonprofit here in town that offers a VERY wide range of classes and workshops. In the summer, programming is expanded to offer even more options for both adults and children of all ages. Registering for a wheelthrowing, moldmaking, or handbuilding class comes with studio access -- and a great reason to hang out with brand-new studio pals. 

If class when school is out isn't really your thing, though, and if you just want studio access, plain and simple, The Clay Studio does also offer studio rentals, which can be a nice solutions for your summer productivity.

Although The Clay Studio is kind of the cream of the crop, plenty of local art centers and community centers feature ceramics departments that may have similar summertime offerings -- check out the resources in your area to see what's out there. In my experience, the people you tend to meet in these settings are an incredibly varied group -- from my own days in community studios, I have friends that I have NOTHING in common with aside from a mutual love of clay -- and that's pretty awesome.

5. Really can't stand to be away from a kiln? If you're in Philly, use our firing service!

That's right. Sometimes, you just need a kiln. Maybe you have the time and space to continue your ceramic production but you don't have a place to fire work. If you're in the Philadelphia area, come to us! We have several different kiln sizes in which to fit your work, and we can carry out any type of oxidation firing you may need, from decal to high-fire cone 10. Check out our firing services details here and please feel free to give us a call at 215-427-9665 if you have any questions at all about how we can help you to finish your work. 

So there you have it -- these are just a few suggestions to help you stay creative during the summer downtime months. If you've found some tricks that work for you during times when studio access might be limited or non-existent, we would love to hear from you! In the meantime -- stay cool!