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Osma Alum Block Astringent (75g)Osma Alum Block Astringent (75g)
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Osma Alum Block Astringent (75g) Osma Alum Block (75g)

Osma Alum Block Astringent (75g)

(62 reviews)  


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Stop bleeding from shaving cuts!

We've all cut ourselves shaving at some point but how many of us know about the wound constricting properties of the Alum Block? This little block serves to contract the tissue surrounding the wound which stems the blood flow.

Boxed Dimensions: 6cm x 2.5cm x 3.7cm

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Average customer rating:
(62 reviews)  

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62 Most useful customer reviews (see all reviews):
Oct 22, 2019
The Shaving Shack verified purchase.
Does exactly what it promises. Leaves clean feel after rinse.Just heads up, it will give you a sting if youve had rough shave.
Mr Alan Haydon Cooper
Jan 28, 2017
The Shaving Shack verified purchase.
Had this a while now and it works so well. Easy to use just wet with cold water gently apply and wait for the magic to happen. Wouldn't be without it.
Mr chris walters
Nov 19, 2016
got this Alum Block with a shaving kit, best thing after shaving , just wet it in cold water for best effect and then rub all over where you have shaved, stings a bit for the first time but you soon get used to it and don't notice after a while , really works if you cut your self and stops any bleeding so no more tissue stuck to your face if your cut , also makes the skin feel fresh , I wait about a min and then just rinse any excess with cold water
Mr Glenn Walker
Feb 26, 2016
The Shaving Shack verified purchase.
Bought this after reading about razor burns and irritation etc and I can honestly say it does what it says on the packet. it stops the little nicks from bleeding all over your white collar eases the red blotchy shaving rash so wish I had found this years ago will recommend 100%
Mr Courtney Higham
Jan 21, 2016
The Shaving Shack verified purchase.
Excellent stuff stings abit but stops the bleeding. Definitely worth having has saved me looking like a cat has scratched m face up
Mr Zoltan Szabo
Nov 5, 2015
The Shaving Shack verified purchase.
Hi there
what can I say the best alum Block ever! :)
I's good forever, perfect part of a rasor kit!!
Mr Peter Jackson
May 20, 2015
The Shaving Shack verified purchase.
If you shave but one of these.
What can I say, well worth it. A quick rinse under the tap and rub over shaved area, slight wake up sting and you can almost hear the pores close with a bang. Afterwards your skin feels clean refreshed and burn free. followed up by Poraso post shave cream you'll feel wonderful.
Neil Proudfoot
May 11, 2015
The Shaving Shack verified purchase.
This is a must buy. It helps stop the bleeding from any minor nicks and it also gives you feedback on your shave, lets you know where you might have made too many passes or used too much pressure. It does sting a little though.
Mr George Christou
Apr 15, 2015
I occasionally suffer from irritation on my neck so I decided to purchase an alum block and see if it made any difference. After a few shaves I started to notice a difference on my neck which was notably less irritated. Alum is now a staple of my shaving routine. It provides feedback after shaving (believe me you will feel the burn if you haven't had a smooth shave!) and is very quick to stop bleeding if you get any nicks.
Mr Jamie Duff
Mar 26, 2015
The Shaving Shack verified purchase.
I've been using the Alum block for couple of weeks, have you admit first time i used it the "tingle" was a shock but it left my skin feeling great no heat what so ever from shaving and to be honest after 2 or 3 shaves the "tingle " is a lot less I've found I'm using the Alum block after ever shave now 100% recommend
Mr Joe Turner
Jan 26, 2015
The Shaving Shack verified purchase.
Being new to DE shaving, I did a lot of research and found that everyone recommended to get some kind of Alum block to help with those beginner nicks! I've been quite lucky so far and not had many issues with DE shaving, but the block really helps stop on bleeds. It also has an added bonus of showing up any areas where you have put on to much pressure.
Word of warning, this thing stings (but in a good way)
Andy Finn
I got one of these in with my razor purchase as i figured there would be a fair few accidents going on with nicks and was the first time using one. It gives you a short sharp sting when it goes over the areas that have been nicked and even areas where u didnt think it was. Just wet the end of it in cold water and run over where you shaved and it really does close those pores quick. It seems to stop any redness soon after a shave aswell. Its guaranteed to wake you up after a shave and keep yr nicks clean i found. Give it a quick wipe in a towel and leave to air dry. Small block but its going to last ages.
Alan Stead
Bought one of these in place of a styptic pencil. At first, I just used it for nicks etc. However, over time I've come to realise that the antiseptic/cooling qualities far outweigh such limited use. These things are wonderful, such an addition to the act. One thing that isn't mentioned in the product description is that the block is composed of Potassium Alum, not Ammonia Alum, ie it's far less agressive. I find that a cold water wash/rince, wet the block, gently rub block over entire shaved area, allow to dry, dab (not rub) with cold rinsed flannel, pays dividends. Always use before after shave of any kind. So much more than the salts on a stick of the Styptic. Looks like it may well last forever too. Well worth it.
Rob Delahunty
These are amazing, true it stings a bit when you apply it to a cut. But the result on a cut is like turning off a tap. Deffinately worth having in your kit for those off days!
Martyn Jones
Haven't switched to DE razor yet but use this in combination with mach3, brush and cream after a two year shaving sabbatical of a full beard. Works really well to stop any nicks bleeding or redness I used to get from hair growing in odd directions. My wife has kindly translated the instructions from the box as they are in French and she is French " Wet the Alum block and wipe slowly over the face after a wet shave or a little time before an electric shave". Hope this helps.
Brian Binns
I got this Alum Block when I started shaving with a DE razor and brush. It is so worth it as it stops cuts from bleeding and closes your pores after a nice hot shave. Much better than using small pieces of tissue where its bleeding, this just closes cuts instantly. I've had mine 6 months and I'd say only (if even) 1/3 of it has gone, it's still got lots of life left in it. The little box it comes in is perfect for storing ot and your current DE blade. Strongly recommend this product.
Ivan Cousins
This is an amazing little block that really refreshes after your morning (or indeed anytime) shave. you can feel it really working closing and tightening your pores.I dont use aftershave because i dont like the strong smell but this product does the same thing without the whiff.
This little block is just simply awesome. Bought it in case anything untoward happened during a DE shave, and now can't ever imagine being without one. Wet the block and run it across any truobling areas...little nicks and "weepers" are just stopped at source. It seems that it will last for ages too.
Nikolaj Hawaleschka Stenberg
The alum block is a truly great addition to your shaving routine! Right after you’ve finished shaving wet your face and the block in cold water and then rub the block against the areas which you have shaven. It stings as mad but also closes nicks and cuts. When you’re done wait a minute or so and then apply your after shave and get on with you day.
Glenn Bautista
This little kid packs a punch... Forget those days when you dabbed your entire face with bloths of tissue paper or white marks left behind behind by a styptic pencil, just rub this natural gem around your damp face shortly after shaving making sure the block is wet and it will magically seal any nicks or cuts that you may have. It also gives you a feedback on certain areas where you went too deep on during your shave, it will sting a little, if man enough to take it but after a while you just become used to sting and it'll be a walk in the park. I highly recommend this product 100% natural and good for both normal and sensitive skin it also take away the redness resulting a shave. The alum block has a long life span providing you dry it after use.
A nice and natural way to protect your skin even after the most aggressive shave.Moreover, it closes little cuts within a second.It doesn't have any smell so, afterwards,you can apply your favourite aftershave.Strongly recommend it!
Martin Jönsson
Does precisely what it's supposed to, and it's a nice finish to your shave. I love feeling the tingle of it on my skin as I rinse out my brush, and it really lets me know where I did things right, and where my angle or pressure was off. The box, as others have noted, is great for storing it or for travel, so don't throw it away!
Chris S
I've made this alum block a part of my every shave. I cannot vouch for its ability to quickly heal nicks and cuts, but applying it after I shave and leaving the residue on my face for a minute or two (it stings!) has noticeably reduced my razor burn. Also, it seems to never diminish or get smaller, so it will last a very long time.

In case anyone was wondering, it does smash if you drop it on a hard floor!
Patrick Britton
First time DE shaver. Youtube videos recommended and alum block and I can see why. Gives great feedback from your shave, you can instantly tell where you might have gone to hard. I had one small nick but this stopped the bleeding very quickly.
Michael Burgess
This is an essential shaving item. You can feel it tightening up your skin and like others have pointed out you get a gentle reminder of the areas where you've overdone it slightly. It doesn't have the harsh sting of a styptic pencil and doesn't leave your face anywhere near as chalky. I wash my face with cold water after shaving, wet the Alum block and rub all over the shaving area. I leave it a minute then rinse off with cold water and splash on some Proraso aftershave, which tops off the shave nicely. Remember to dry it well before you put it away to prolong it's life. Definitely worth the money.
James Clarke
I unfortunately bought one of these elsewhere before I found this website. The price was much near to the £10 mark and didn't get any reward points. When I was new to DE shaving I just used this for cuts. But now I use it after my shave to close the pores aswell. At the same time you can feel the areas that you cant see or feel before using this that have been irritated when your new to DE shaving and helps you to take care next time you shave.
Patrick Higgins
A brilliant product which finishes a good or bad shave and makes both much better.
Its very refreshing to use, and as others have stated, very informative as to where you have upset your skin. This item adds a real sense of completion to your daily shave.
Thanks Shaving-shack for quick delivery and another top product.
Craig Carroll
Stings like hell, but does stop any persistent nicks. It's a decent size block, and as long as you don't slice your face up every shave, it's bound to last for years and years.
Stephen J Baker
I'd never even heard of an Alum Block until I saw it recommended at the Shaving Shack. Glad I bought it. Now its part of my post-shave routine. Simply wet your face and rub. It stops any minor nicks without stinging as much as a styptic pencil. Tastes strange but perhaps I should close my mouth when using it.
Neil Robinson
Seems to work better than styptic pencil, just rub it all over after you've finished your shave and rinsed, and it takes care of any nicks or weepers. If you cut yourself really bad, wet the block, rub it in then prepare to hurt. But at least the bleeding stops. Could do with a nice piratey logo like the bluebeard tackle, but you can't have everything can you.
Neil Goodhead
Would never have believed the effect that that this little block could have. A cold water splash after a shave then rub the block over your face and you can really feel it tightening the skin and closing the pores. Highly recommended!
Norman Somerville
I can only agree with the positive reviews here. If you are going to wet-shave, get one. You will soon find it is indispensible.
Clive Pepper
After one month of DE Shaving Experience I needed some blades so decided I'd add the Alum Block to my armoury (well might as well get your order up to £40 and get free postage, that's my excuse anyway!)- I'm so glad I did! This has quickly become a firm favourite in my daily shaving routine. At the end of the shave I do a warm rinse, then a cold rinse, then wet the block before running it over my entire shaving area. I'd read it 'finds' anywhere you've maybe gone a bit too close with - apart from the benefits of the Alum itself (you can feel it tightening your face, it's great!) also is like a 'meter' to tell you how well you've shaved! Gone a bit too close, it delivers a nice sting to tell you (short lived and provides instant relief). Where I've been pleased is I've studied lots of videos on getting the right blade angle, but now as I've not had too many 'stings' from the block, I'm getting more and more confident my blade angle during shaving is correct, so it's way more than just something to fix your face after a shave! This a fantastic piece of kit (will last forever), just get yourself one, highly recommended!
Adam Cockerill
I am recently new to straight razor and DE shaving, after looking around at a few shaving routines I decided to get one of these, when you use it on nicks they disappear!! very good product that helps give you feedback so you know where to be less aggressive next shave. stings a little but a must for the perfect shave.
Robert Jackson
I'm back to DE shaving after a time away frittering away my hard earned cash on disposable razors - I'd not tried this alum block before but I am now wondering why not - it's the perfect finish to your shave - tightens the skin up and followed a few minutes later by a witch hazel / tea tree oil mixture completes the job nicely.
James Riley
Bit of a mied bag, this one. Found that it stops some cuts, but only tiny ones from bleeding. Does not seem to reduce irritation either. I guess it shows you where you need to be a bit more easy going next time. Would like to pay more if it came in sme kind of waterproof container for traveling too. If someone knows of a small container that will fit this, please let me know.

Chris Maguire
Ive never used after shave before, because of the strong scents. After a shave I usually just splash my face with cold water to close the pores. But after reading about the alum block I thought I would give it a go. I noticed people were saying they soak the block, so I did just that before applying to my face. I couldn't really feel anything at first but then on my neck I could feel a slight sting, where i must have gone a bit to close to the skin. Judging by this, i should have got slight shaving rash but instead I got nothing, so I would say this is an essential in any shaving kit. Will teach me to shave better too.
Neil Jary
Purchased one of these to add to my new collection of wet shave gear. First up I was surprised by the size of it...I was expecting something the size of a soap bar from the photo..but it's really small...not much larger than a matchbox!
Having said that, don't be fooled! It's amazing!
I jumped straight in after my shaves and opted to use it for a complete after shave treatment rather than just to stop the bleeding of occasional nicks.
I have psoriasis so a cut is something I would expect no matter how careful I am..and with my new shavette they are a certainty!
I shaved, rinsed with warm and then cold water and then dipped the block into water and rubbed it all over my face! WOW! What a tingling followed by an almost menthol cooling! The couple of nicks I had stopped bleeding almost instantly and after I minute or so I could feel the skin on my face tighten! It felt really good! Invigorating, refreshing and calming on any razor burn!
Truly superb and a must have purchase for any wet shave!!
Arwel Jones
Started using this while i was still shaving with cartridge razors and did not see the point of it. It just did not seem to do anything, but since i have started using DE razor my god does this thing work!! It is a must have to finish your shave. It closes all your pores and seals those nicks instantly. Highly recommend this product.
Neil Ord
I was a bit sceptical before I tried using an alum block, but it is now a key part of my shaving routine. Warm shower, wet shave, warm flannel to rinse, cold water splash and alum block = perfect shave.

Useful as a newcomer to DE shaving, as any sting will give you an idea of where you were too aggressive. Takes care of any minor nicks.
Bought this with my first DE razor and would recommend to all razor users. Works very well when wetted and rubbed directly on affected area. Calms affected areas and stops bleeding very quickly. I still have the same block after around 4 years and it looks like it may last another 40.
Trevor Hare
The £6:69 facelift! Alum block, looks like marble, rub it over a wet face after shaving. Instantly stops any little cuts/nicks. Stings like hell, but the upside is, it tightens your skin like it was 5-6 years ago! Bloomin' miracle!
Simon Daniels
A very good product; it does close up nicks very quickly and it does sting, but, only where your technique has let you down and you have gone to close. If you shave carefully, even with a Feather or an Asco blade the block just closes your pores without pain. Excellent, and, as everybody says, it will probably last for years. Highly recommended.
Alan Fleming
I'm new to DE shaving and bought alum block as part of my first order with Shaving Shack. After first ever attempt at DE shaving I was not sure what to expect having read some reviews. Wet the block and rub directly onto the skin and it stops any bleeding and reduced the redness very quickly. Absolutely one of the best components of my shaving process and will last ages.
George Thompson
Ive been DE shaving for about 2 years - at home and with the barber. The barber used a pencil - but I bought one of these a couple weeks ago ! absolutely amazing piece of kit! I posted in on Facebook and have been told by friends that it is also great as a deodorant! I wouldn't be with out it in my shave bag now! Im going to tell my barber too!
Colin North
Just the dog's bollocks. Perfect end to a shave - you've got to get one. Shame no plastic box though... (I travel a lot)
Very please with this product bound to last me years!,shame thou it doesn't come in a little plastic container
Petteri Aaltonen
Cheap as this seems to last years and years to come. Worth having even if you dont plan to use it after every shave. Closes small cuts right up. No odor, just rince under cold water before and after use.
Mike Howells
Yes it closes up the inevitable nicks that you get as a novice DE shaver (and, one assumes, as a more experienced one with a twitchy hangover), however, it's also a nice thing to use anyway. You know that mint and tea tree shower gel? (What am I saying, of course you do, and you know *exactly* what I'm talking about.) Well, it's like that, but for your face. Now used every time I shave, blood or no blood.
Steven Batty
What a fantastic product. Used it this afternoon after my shave and what a way to end a shave. Would highly recommend one of these as part of your wet shave routine.
I use this alum block after every shave, it soothes any irritation and closes any small nicks. Just wet the end with cold water and rub it over your face to give a brilliant end to a shave.
Stephen Palmer
I got one of these to seal up the small nicks that I got and deal with any irritation. It works great, just wet your face with cold water, run the block around and leave for a minute or two. Then rinse off and apply post shaving cream. Job done!
Ryan Martin
I'm glad I bought this product, I nicked myself and had this to hand and it just stopped bleeding! Yes there was a slight sting but it's survivable for sure. Might just carry this around all the time
Andrew Dempster
As a newb to DE I got this due to the very positive reviews. Some days I need it (possibly due to beer related late nights). Some days I don't need it.
Buying a second because although it will last forever, where the heck will I get a back up come the Zombie apocalypse?!

And the box is pretty ;-p
Andrew Sanaev
I bought it because I thought that I would cut myself a lot during the shave but it didn't happen. So now I use it before and sometimes after the shave (instead of post-shave cream) because it helps me to liquidate pimples on my face. Would recommend.
John Ross
Tried, Trusted and True. The Alum block has of course been around for a long time as a shaving aid. That should give us a clue! It works!! It is a must have in my shaving gear. I have recently bought one of these for my 30 year old son who was skeptical at first. "Dad it can't possibly work it's only a block of crytsal!!" was his first comment on seeing it.. Now he swears by it. I always use it with cold water after a cold rinse when it seems to be most effective for me.
Highly recommended. Get one! It will last ages and ages so is cost effective as well.
Niels Graudal
I have been using one of these since august 2012, now it is almost june 2014, and I think it will last all the way to august, even though it has shrunk a lot lately. Two years of use for under £7 is a steal. So I just ordered another, simply because it is as necessary for me as the razor and brush.
After the shave a quick rinse with cold water and then the use of this will let you know where you have been over-enthusiastic with the razor. It is the perfect companion to avoid a rash, and to let you know where you need to improve your technique.
Geoff Hinchliff
Lasts ages!

Had one of these for over a year now. Run under cold tap after shaving, rub all over the shaved area and leave a couple of mins before rinsing off and no irritation! Follow up with a good balm and you're away.
martin mullett
good Alum Block for you
David Wright
Purchased this in November but only recently needed to use it.

Item is amazing and stops most shaving cuts in seconds. I’ve also found that is reduces shaving rash if and when you get it almost straight away. Well worth keeping in your wash bag just in case.
Ben Laidler
Does the job exactly as advertised! I have integrated this into my shave routine rather than just using it for nicks and cuts. I find it best used once to have completed your final pass, rinsed and rubbed directly onto a wet face for instant feedback on your shave. It's natural properties should help reduce any irritation and close up your pores post shave.

To all the people that say it stings, well yes it does but it's hardly painful so don't let that put you off using one of these.

Dry it once you have finished using it and store it back in the box it came in. I have used mine 12-15 times now and it still looks new so it should last for ages.

Connor Clarke
Brought this mainly for small nics when shaving but also because my chin becomes particularly sore and spotty after shaving and wondered if this would help with its antibacterial properties. Since using it I've noticed fewer spots overall and my chin no longer becomes sore and spotty after shaving. Stings slightly on initial use but not to much and is brilliant at soothing the skin post shave.
Earn 15 points (equivalent to £1) for every product review you write that gets published on this website. Please note that we reserve the right to accept or reject reviews and there is no guarantee if and when a review is published. Only registered customers are allowed to add review, please sign in and share your experience!

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