Alum Block: Health Risk & 5 Ways To Use Efficiently

Alum block is one of the accessories and tools used in shaving, this is has been used for a long time and can stop the pain, irritation and inflammation associated with shaving. According to history, the Egyptians used potassium alum for more than 4,000 years ago for its antiseptic and healing properties and to cool and revitalize the skin.

It is a mineral block that is made of potassium alum and has antiseptic and astringent properties. The astringent properties can help to reduce inflammation and bleeding after shaving and the antiseptic properties of the alum block protect the skin against disease-causing micro organisms. Alum block can also prevent ingrown hair. 

It looks like a crystal stone and is shaped like a miniature bar of soap, it can also be in different shapes and sizes. The block is also known as an alum crystal or alum stone. This block can help reduce razor bumps that appears after shaving, minimize redness and razor burns.

Many people mistake styptic pencil to be alum block. Although they are both post-shaving equipment, there are differences between both. Alum is used for minor razor cuts that may occur during shaving, it can reduce bleeding and inflammation, act as natural deodorant and stays longer. Alum block can also be used to treat acne.

Styptic pencil is also used to reduce bleeding after shaving but they are mostly used for bigger and more serious cuts. This means that it is not only used for shaving but to treat most serious cuts. They have lesser shelf life than the block.


Apart from being used as a post-shaving equipment, there are other uses the alum block has.

Alum Block for Acne and Dark Spots

Any product that treats acnes must be able to exfoliate, clean, and tighten the skin, this is why salicylic acid is added as a major ingredient in most products. An article by Emerging Microbes & Infections in 2016 showed that alum has compounds like salicylic acid in it. This means that alum block has the ability to clean bacteria and tighten the skin.

Alum Block as a Deodorant

Deodorants and antiperspirants are used to reduce how you sweat and also help to get rid of bacteria around the armpits. Some natural deodorants are made with potassium alum like the crystal deodorant. It has the properties to keep your armpits fresh and killing bacteria also. In fact, most crystal deodorants in the store are just slightly refined versions of a pure alum.

Alum Block after Waxing

Waxing is most times preferred as it reduces ingrown hairs appearing after shaving and also, there is no risk of having razor burns and cuts. However, waxing can cause irritation especially if it was done roughly or if the wax was too hot. This makes the antiseptic and astringent properties of alum beneficial for freshly waxed skin as well.

Other uses include

  • Clearing up pre-existing skin conditions like acnes or spotty skin for a better appearance.
  • Calming the skin and avoiding razor bumps for women after shaving sensitive areas like the armpits and vaginal area.
  • Improving skin tone, most people notice their armpits or other shaved areas becoming dark with time.
  • Using alum on the shaved area can reduce how it darkens and tone it up.
  • Increasing grip on slippery safety razors or straight razor handles.
Alum Block


1. After shaving, make sure your face or any part you shaved is clear of any remaining soap or shaving cream. Splash water on your face to close the skin pores and tighten them. When the skin pores are closed and tightened, it will be easier to be exfoliated.

2. Use cold water to wet the alum before you run it on your face or any area. Make sure the entire surface is wet. You can soak the block in ice water before you use it for an increased cooling sensation especially if you’re prone to nicks, cuts, or razor burn. Or if the razor blade wasn’t as sharp as you would’ve liked (Grown man Shave).

3. Rub the block on the areas of your neck, face or any other part that you shaved. You should massage the area gently. You can feel tingling, mild burning sensation  and your skin tightening a bit, this is because of the astringent properties the block has and the salicylic component of natural potassium alum doing its function.

4. Let the alum be on your skin for about 15 to 20 seconds. If your skin is sensitive, you should only allow it be on you for not more than 20 seconds. The time the alum residues sit on your skin is to allow the properties to clear your skin and tighten the pores. After the time, rinse with cold water.

5. You can apply moisturizer or after-shave products like high-quality moisturizing cream, aftershave, or shave balm made with natural ingredients. You should pat the block with a dry towel after using it. You can also leave it on a safe, dry surface to dry completely before the next use.


Storing alum block is very important because exposing your alum block to moisture or leaving it wet always can make the crystals to start dissolving. Also, storing it properly will increase its lifespan. Alum blocks are mostly for immediate use, not really great for long-term storage.

Patting the block dry with towel before storing is a good way to store your alum block. Also, storing the alum block in a cool, dry place with access to adequate airflow is also good. If your alum came with a plastic case, use that for storage.


There are many shops that sell alum blocks especially where shops that sells skin products. You can also check online shops that sell professional shaving products and kits, they will sell alum blocks. It is important you buy from known shops and stores so as to get high quality alum block. High quality and finely made alum bar can be used for years.

Buying poor quality alum block is not encouraged because poorly made alum stones can start falling apart bit by bit and all you are left with is a pile of dust.


Alum block has many benefits but there are also some precautions and health risks. You can get some burning and tingling sensation when you apply alum block. Although it is normal, if you have low pain tolerance, you may not find the burning sensation funny.

Alum block can cause irritation on the skin and this may not go away even after washing the residue away. This rarely happens but if the irritation continues, it may mean you are allergic to alum, you should see your doctor before continuing usage.


It is not advised to be used everyday although you can use everyday. If you have a sensitive skin, using an alum block everyday can make your face become dry. But if you have an oily skin, it can be okay to use everyday as alum has astringent that can draw moisture from the skin. Using the alum block always can make your skin produce more oil than it naturally would because of the antiseptic properties it has. This can make your skin become more greasy.


How long your alum block lasts depends on the size you bought, how you use it and how it is stored. A standard 50 to 70-gram block can last for two years and more if you care for it properly and use it once a day.


You can use both if you want, some people like to combine both while others do not. It lies on your preference. Some people claim the combining the both products are not good for their skin as the alum’s astringent properties and the alcohol content of aftershaves tend to dry out their skin. You can use the aftershave and the alum block separately to know which is better for your skin.


Alum block is used for antiseptic and healing properties of the mineral, it acts as a natural coagulator, astringent and antiseptic. It is usually used after shaving to heal minor cuts, reduce inflammation and bleeding by constricting the blood vessels. It can also tighten and clear pores thereby clearing acne and other skin conditions.

The alum blocks come in different shapes and sizes. You can get a big block of 50 or 70 gram if you’re just using it at home as part of your regular shaving routine, but you can also get a smaller bar for travel or a more precise application. Use the correct way of applying this crystal block to get the most benefits. However, you should see a doctor if you feel irritation after using the product.

error: Content is protected !!