Clumps or Crystals: Which Cat Litter Type Works Best?

I would argue the only drawback to having a cat in the family is also having a litter box… potentially several litter boxes. You need to find a place to put them, which can be especially hard in smaller homes like apartments, and you have to decide which litter to put in them and there are dozens of options to choose from.

Options are great, but where do you even start when trying to select a cat litter?

There are really two broad categories of cat litter, clumping and non-clumping. Most pet parents reserve non-clumping litters for baby kittens and choose a more convenient clumping option for their adult cat.

In today’s post we’re going to dive into the different types of clumping cat litter and weigh the pros and cons of two competing options, clay versus crystals.

Which will win? Let’s find out.

What are the Different Types of Litter?

Today, there is a wide range of different kinds of cat litter. The most traditional is made of clay, but there are also crystal cat litters and a variety of other kinds such as:

• Clay litter, the most common option on the market, and it’s made from bentonite clay. One of its major selling points is it’s typically the cheapest cat litter option available.
• Crystal litter, is made from the mineral silica. While similar in performance to clay litter, it tends to be quite a bit more expensive.
• Corn litter, as the name suggests, is made from dried, compressed corn. It’s the largest crop grown in the US, so there’s no surprise that they found another use for it. Corn litter does a good job with odor control.
• Pine litter, which is made of renewable wood, can be very absorbent and tends to track less, leaving more litter in the box and less on your floors.
• Wheat litter, which is made of processed wheat husks as a byproduct of wheat farming and tends to clump quickly.
• Paper litter, which is essentially made of pellets of (typically) recycled, compressed paper. While this litter is low tracking and low dust, it doesn't do much in the way of odor control or absorbency compared to other litters.

This isn’t an all-inclusive list. You can also find litter made from tofu, grass, pea husks, etc. though these tend to be less common. For now, I'm just going to compare the two most common kinds of cat litter: clumping clay and crystal.

What is Clumping Cat Litter?

Clumping cat litter is cat litter made out of dried-out pellets of clay. Clay, if you've ever played around with it in nature or in a crafting or art class, is basically dirt and water. However, unlike something like mud, clay has more substance to it. Dry clay, like what cat litter is made out of, can absorb up to its own weight in moisture, making it very good at absorbing cat pee and the more liquid aspects of their number twos.

When clay pellets are dry, they're like tiny stones or sand. However, when they get wet, they absorb that moisture and stick to nearby dry clay. This is the "clumping" effect; the bits of clay that get wet clump up into one mass, which can be easily scooped out of the remaining still-dry pellets. Cat poo, since the outer surface is wet, will get coated in clay as well.

Clay is also an inorganic material, which means there's nothing for bacteria to feed on. It's not necessarily antibacterial, but it does have some odor-control properties. Clay also has free hydrogen atoms that attract some of the more acrid and powerful odor-causing molecules in cat pee and bind to them, trapping it.

The Benefits of Clumping Clay Litter

Clay litter can be scented or unscented, and some clay litters can even be non-clumping, but we're mostly concerned with clumping litter today. So, what are the benefits of clumping clay cat litter?

It's very easy to clean. A litter box full of dry pellets, where the waste clumps up, is easy to clean. The clumps can easily be scooped out with a slotted scoop, which usually comes with a litter box. There are even mechanical or robotic litter boxes now that can automatically scoop and clean themselves when they detect your fur baby leaving their enclosures.

They have quite good odor control. Scented cat litter has an odor of its own, but unscented litter just traps odors and dramatically reduces the "impact" of a litter box on the surrounding room and environment.

It's cheap and easy to find. Every single pet store is going to carry clumping clay cat litter just because it's the cheapest and most readily available kind of cat litter. Clay is readily available pretty much everywhere in the world, so it's not exactly a scarce resource.

It doesn't go bad. Some alternative cat litters, like pine or tofu (yes, tofu litter is real), are organic materials and can rot or mold, especially if they're stored in humid environments or they get wet. Clay cat litter is just clay, and clay doesn't really go bad. In a way, clay kind of is the end result of things going bad over millennia.

The Drawbacks of Clumping Clay Litter

Despite the benefits, there are a few serious drawbacks to clumping clay cat litter, which is why more alternative cat litter is being developed.

It's dusty and easily tracked outside of the litter box. Clay litter is dry dirt, and those little pellets can abrade against one another or break apart, leaving clay dust behind. This dust is impossible to get rid of – you can't exactly wash the clay without defeating the purpose entirely – so every bag of clay litter is going to have dust in it. The dust and the litter itself can spread and get all over the place, especially if you have a messier cat.

It can be very heavy. Seeing as it's just a heavy kind of dirt, clay can be heavy on its own, and when saturated with waste, it's even heavier. Hauling a bag of dirty litter out can be surprisingly difficult. Moreover, the sheer weight can risk tearing through weaker baggies and other containers. What cat parent hasn't had a bag rip open and catastrophe to spill out?

Clay cat litter isn't very eco-friendly. Part of the reason why eco-friendly alternatives are being developed is that clay litter is decidedly not eco-friendly.

• It's created largely through strip mining, which can devastate an entire region of the planet.
• It doesn't biodegrade, so that clay ends up sitting in landfills basically forever.
• It can spread cat-based parasites and diseases like toxoplasma gondii to areas where it is dumped.
• In some cases, build-up and runoff can damage local watersheds.

Of course, eco-friendly options are less widely available and more expensive. Isn't that always the trade-off?

Finally, it can be carcinogenic. Most clay cat litter is made of bentonite, and bentonite itself is mostly harmless. However, some bentonite can include some amount of quartz, and that quartz, when broken down into dust and breathed in, can be carcinogenic. Remember that first con listed above? Yeah, unfortunately, there's some evidence that it could be dangerous to both people and our feline friends. It's not the worst substance in your house by any means, but it has the potential to be bad over the long term.

What is Crystal Cat Litter?

Crystal cat litter is named because it looks a lot like tiny crystals or granules of shattered glass, except it's nowhere near as hard or as sharp. It's a non-clumping litter, which means solid waste sits in it, and liquid waste is absorbed into it, but the individual "crystals" don't stick together.

As you might imagine, this means you can't really just scoop out clumps and leave the rest alone. You can scoop out the solid waste, but sooner or later, you're going to need to discard the whole batch and replace it when it gets more saturated.

Crystal cat litter is made of silica gel. Do you know how sometimes when you order a product, it arrives with a little packet labeled "desiccant" with big "do not eat" labels on it? That's usually silica gel. Silica gel is basically the same thing as quartz but in a different form, which is why it's not sharp or rock-like the way quartz is. It's extremely porous and very, very good at absorbing moisture, along with molecules attached to that moisture.

Crystal cat litter is a decent alternative to clay cat litter, but it has some distinct drawbacks that might be deal-breakers for you.

The Benefits of Crystal Cat Litter

There are a few really good benefits that make silica crystal cat litter a useful option.

It's low dust. Silica gel doesn't break up into dust the way clay does, so while there may be tiny particles around, it's not going to billow out the way clay does.

It's light. Silica gel is a very lightweight molecule, so it's much easier to move around – both dry and wet – than clay cat litter.

It has very good odor control. Clay is also good at controlling odors, of course. The two are kind of the same, though, as you'll see from one of the drawbacks, it has a breaking point.

It's non-toxic and low maintenance. While every litter box will require daily attention, crystal cat litter is generally considered to be a little less maintenance-heavy than clay, though for some people, it's a personal preference.

The Drawbacks of Crystal Cat Litter

So, what about those drawbacks?

Crystal cat litter has a saturation point. With clay cat litter, it's obvious whether or not it works. If it's clumped up, you remove it and replace it; anything not clumped is still good. With crystal cat litter, it can absorb up to 40% of its weight in moisture, at which point it stops. The problem is that there's no visible way to tell how close the litter is to saturation. Worse, once it reaches saturation, new cat pee will just filter through and pool at the bottom, creating a smelly mess. You either need to proactively change the litter frequently or deal with these sudden explosions of waste.

It's easily tracked by your kitty. Silica gel is easy to spill and track around the house, so it can make a mess, particularly around the area where you keep the litter box. You can contain some of it by putting the litter box in an enclosed space, but that makes it harder to notice when it reaches the saturation point.

Some cats don't like the texture. Crystal cat litter can be rough and abrasive, and some cats – especially those with sensitive paws or paw injuries – won't want to step on it. A cat that doesn't like their litter is going to go somewhere else to do their business, and that's an unpleasant surprise you never want to discover.

It's also not eco-friendly. Being silicon, silica gel doesn't biodegrade, just like clay. It's also mined as quartz, and the quartz goes through a chemical process to turn it into silica gel. All in all, it's pretty intensive, not great for the environment, and not great for the local landfills.

Finally, it's comparatively expensive. While it's not as expensive as the more exotic organic litter materials, it's going to cost you more in the long run than clay litter.

Which Cat Litter is Best?

So, what cat litter is the best?

There's not really a clear answer here, so you need to ask yourself some questions.

First of all, how much do you care about the environmental impact of your cat litter? Neither clumping nor crystal litter is very good in that sense, so you'll probably want to go with renewable litter instead.

That said, clumping cat litter might be the slightly better option. Since you can scoop out the clumps and keep using the non-clumped litter for quite a while, it's a pretty decent option to use just the minimum amount at any given time. Silica, on the other hand, you'll need to toss out and renew more often so you go through it a little faster.

How much do you care about the cost? Silica/crystal cat litter is marginally more expensive, so if you're budget-conscious, clay litter is probably the way to go.

What is your cat's preference? Really, this is the biggest deciding factor. Get multiple litter boxes, fill each with a different kind of cat litter, and see which one your fur baby decides to use. The best cat litter is the one that works for your cat, after all. Some cats have sensitive paws, don't like the smell of a certain kind of litter, or don't like the feeling of digging in it.

Moreover, if you're in a multi-cat household, each cat may have their own preference. Since it's usually a good idea to have one litter box per cat (plus a backup), you can stock them differently according to their preferences.

What cat litter do you find the best? Let me know!