When trying to get the most comprehensive wet shaving experience, you may have heard of something called an ‘alum block.’ What is it? What does it do? Do you really need it? Did you really just mishear it, and someone named Alan Block just wants to help you with your shaving? Well, all of these questions and more will be answered for you below.

What is an Alum Block?

First off, just to get this out of the way: no – Alan’s never even heard of you, so you don’t have to worry about him. An alum block, however, is a little brick of the compound ‘alum’, also known as hydrated potassium aluminum sulfate (or potassium alum).  This particular compound is a water-soluble and acidic crystallized astringent that is great for any number of uses. Back in the Roman days, it was used to purify drinking water, and is still sometimes used to day in industrial processing of water. You can really think of it as the first aftershave, where instead of using god knows what artificial chemicals you might find in there, you’re just using mineral salts that have been around since the Earth was formed. People have been using this stuff for literally four millennia, and for good reason – it really does the trick.

The way alum works is, it is able to attach to negatively charged colloidal particles when added to water, which allows impurities to float to the top for easy skimming and removal. This is a great and inexpensive way to filter and disinfect water, making it perfect for cleanliness and potable drinking sources. Of course, you didn’t want to just hear about how you might want to chuck your Brita filter for an alum block, right? You’re here to hear about wet shaving and how alum might actually help you there. Well, keep a’reading!

How Do You Use It?

Alum blocks are not entirely dissimilar to styptic pencils; in essence, both are used to heal nicks and cuts that come from wet shaving. However, while the pencils are mostly cut-specific, you can use the block (which is bigger) in a more general sense to rub over the area you shaved in to deal with more general problems, like razor burn. Also, the antiseptic nature of alum blocks will have a cooling balm effect on the skin, leaving you refreshed and feeling great after your shave. It’s a really helpful thing to have regardless of whether or not you’re worried about your safety razor or DE blade catching your skin.

Using alum is easy as pie, and we’ll tell you just how to do it. After you’re completely done with your shave, just open the block and take it out of its wrapper or container, and run a little cold water over it to get it moistened. Then, take the block and place it over the area that you shaved, rubbing it in a gentle fashion. You don’t have to worry about clockwise or counterclockwise or anything, just make sure to cover the area you want treated with a decent amount of the mild lather you’ll end up getting from the block.

Once that is done, don’t wash off the solution right away; leave it on your face to dry for a minute or so. After you feel like it’s dry, go ahead and splash some water on your face, and pat your face dry with a dry towel (don’t rub too hard, as you want some moisture left on the face. Once that’s done, put on your typical moisturizer or aftershave balm to finish the process. Alternatively, if the alum block is the last step for you, just leave it on without washing it off. Simple, right? You can’t possibly mess it up.

Alum blocks are good for more than just making your face feel nice, though. Alum works to heal nicks and cuts by becoming an astringent – what that means is that it will tighten the pores and constrict your blood vessels, making your face get better faster than without it. (Remember to get your face nice and moist before you do this, though, as it might make your face TOO dry and then you’ll have quite a few problems with your post-shave.) If you’ve got skin that’s greasy or has spots, you can use alum on this too; it will mop up the grease and dry you right up – so if that’s what you’re looking for, you might actually be in luck.

One last thing you should keep in mind: don’t use your alum block every day. For one thing, you don’t need to; a little grease is good for your face sometimes. It’s a nice backup deodorant if you want to keep yourself smelling nice; just rub that bad boy on those armpits in order to give yourself some sweat and odor protection if you need to. Also, when you dry out your skin too much on a regular basis, your skin will start to overcompensate for it my manufacturing a greater amount of oil. You’ll just end up making your face greasier. Stop it!

All in all, an alum block is an amazing thing – it helps get your skin dry, it will stop you from bleeding from those unfortunate cuts, and is just an all-around good resources to have on hand. It’s all natural, it works like a charm, and it’s got a sense of tradition that will keep you feeling connected to the past. Luckily, if you want to get started, we put together a nifty guide to some of the best alum blocks out there to help you make your choice.

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The Art of Shaving Alum Block, Unscented

The Art of Shaving puts together some amazing shaving products all together, so it’s no surprise that their alum block is nice as well. While, for the most part, all alum blocks are made of the same stuff, it’s the little differences that make it worthwhile, and the Art of Shaving block is a winner in that regard. First of all, it comes in a nice striped grey-and-black box that will go nicely along with the rest of your shaving kit; if you’re a smart shopper, you have some other Art of Shaving stuff already, so it probably already matches!

The bright side of this alum block is that it works like it should; this is made of the real stuff. Just rub it on your face as soon as you get that nasty nick, and it’ll get to work right away in healing whatever cut you may have. The downside, however, is that it’s pretty overpriced at $20; you can probably get cheaper blocks elsewhere, but the Art of Shaving offers reliability, so you can’t be blamed for checking it out.


Gentleman Jon 3.5 Ounce Alum Block

For something a little more reasonably priced, but at about the same level of effectiveness, you can’t go wrong with the Gentleman Jon alum block. This one’s got a particular sense of history to it, which is almost worth the purchase alone; Gentleman Jon is a real guy, whose father was a blue-collar carpenter who taught his son how to wet shave, and he started the company and styled it with its classy, vintage 1920s aesthetic in honor of his hardworking dad. Brings a tear to your eye, doesn’t it?

Well, as heartwarming as that story is, the Gentleman Jon block’s effectiveness backs up that sentiment with sheer quality. It’s a really good, effective alum block, giving you a hefty 3.5 ounce block for just $6. It’s an incredible deal, and one well worth checking out. It doesn’t do anything that other blocks won’t necessarily do, but it definitely is worth the money you save.


Bloc Osma Alum Block

If you want a different flavor of vintage in your alum, Bloc Osma has a nice 2.65 ounce alum block on sale for about $7 as well. Made in France, it’s got that sort of European flair in its packaging that makes it feel that much more exotic – the two-tone parchment color and dyeing to its box design transports you right back to the 1920s, and it really matches the old-style shaving kit you might be building.

There are a few downsides – unlike the Gentleman Jon block, it doesn’t come with a plastic case, so you don’t have anything that will effectively store it unless you already have something to that effect. Furthermore, at $7, it offers you about an ounce less of alum than the Jon brand, so if you’re worried about cost-effectiveness this may not be the product for you. It works great, though, getting those nicks and cuts healed in record time. It’s up to you whether you value style over … well, value.


RazoRock Alum Block

If you’re looking for something a little more extreme or unconventional than the barber-shop style looks of the first three choices we’ve given you, the RazoRock might just be up your alley. Instead of being a literal rectangular block of alum, the RazoRock comes in a unique cylindrical shape that makes it a bit better for gripping and rolling onto the contours of your chin.

What’s more, there’s a little plastic handle on the bottom that you can hold; there’s no fear of wasting any alum on your hands! I, for one, think that’s a great, cost-effective move, as it gets the alum where it needs to go – on that nasty cut you gave yourself because you weren’t paying attention. I think the coolest part of the plastic handle is the little hole on the bottom that lets water leak out so it doesn’t accumulate under the plastic.

It’s a great way to prevent trapped water from letting the block get worn down any more than it should be.Now, at $9, it’s still a bit more expensive than the more reasonably-priced blocks we’ve shown you, but the plastic handle and more cost-effective design make it doubly worth it.


Shavex 125g Alum Block

Last but not least, we’ve got the Shavex alum block. The thing I like most about this block is the size; it’s 125 grams, which translates to 4.4 ounces. That’s way more than even the Art of Shaving block gives you! At about $10.50, that makes it an awesome value, as it will last that much longer than anything else you’ll get, and it also comes with a plastic case that will let you hold on to the bar as long as possible.

The only downside I can reasonably think of is that it might actually be TOO big; if you don’t expect to use it often, or make it a regular part of your shaving routine (which you shouldn’t), you might think the giant bar takes up too much sink shelf space. Still, if you can store it elsewhere and just take it out when you need it, it shouldn’t be too much of a problem. Simply put, this one is an awesome deal.

There’s a whole world of other alum blocks out there just waiting for you to check out, but these were some of the ones that stood out to us. While they’re all made of the same essential ingredient, the difference in shape, size, packaging and value are enough to make this a very good start to your journey. Good luck!


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Image Credit: BLOC D’ ALUN” (CC BY 2.0) by daveoratox

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