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Prevent and Remove Mold From Old Leather Belongings – 7 Useful Tips from a Preservation Expert

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By Natalie Miller, Guest Blogger

Mold can be found everywhere. Those microscopic furry organisms come in different forms and colours, and they can and do colonize anything – including your home, the contents and tragically, your treasured heirlooms. Mold can cause serious damage and it is particularly dangerous to old leather book bindings and other leather heirlooms. Here are 7 useful tips on preventing and cleaning mold from your old leather belongings… An important 1st Tip!: old leather is much weaker and more sensitive and you cannot clean it the same way or with the same products as new leather!

Leave stains along for now

Get good air circulation to dry out mold

Tips#2 Prevent new mold growth; get lots of airflow Mold reproduces in a warm and humid environment. That’s why you should make sure that the places where you store old books have adequate air exchange. During the warm months, turn on the air conditioner and lower the temperatures. If you have a fan, you can use that as well. It will help you decrease humidity and ensure enough airflow.

Tip#3 Prevent new mold growth; Get a dehumidifier Folks who live in chronically humid areas know the value of such devices. Don’t under estimate the value and effectiveness of this useful invention! They can be purchased for a reasonable price and it can save you in case you have too much humidity at home and especially in the areas where you store treasure family heirlooms.

Tip#4 Check your storage areas for humidity build up as the weather changes. High humidity is bad for any art, antiques and collectibles…but especially do not store any old leather items in humid places with stale air. Mold loves leather and the glues that bookbinders and furniture makers use. Dark,forgotten, unused basements are flat out bad places for cherished documents, books, artwork and antiques. Many closets or basements have an exterior wall, which will cause frequent temperature changes and humidity. Also, check the storage area for any potentially leaky pipes (for instance, don’t store boxes of stuff under pipes and be sure to keep boxes of stuff up of the floor). Those can result in mold colonies and, of course, lots of damage.

Tip#5 Prevent new mold growth; Be careful with wrapping. Never wrap or seal old leather in plastic if it is humid (whether you are using plastic wrapping or putting things in a plastic storage box). Dry the item out first. Sealing it so it cannot breath while its humid will prevent access to air and serve as a perfect environment for mold development.

Don't throw the baby out with the bathwater!

Poor storage in damp areas will ruin your treasured documents, old books and keepsakes.

Tip #6 If you have mold on old leather items, tremove it do this:            

a. Dry out the items with lots of airflow and see if you can stop the humidity (turn off leaky pipes, turn on a dehumidifier etc)DO NOT raise the temperature of the room or area. Drying leather items out in a hot oven will ruin the leather as will putting it out in the hot sun. Trying to dry something out by raising the temperature of the room will accelerate the mold growth.            

b. Get personal protectionbuy a dust mask (minimal protection) or a mask with a charcoal filter (much better) and wear plastic gloves like surgeons wear (these can be bought from most hardware stores as many construction-type job experts wear them). Wear long sleeves and cover your hair. This is all a precaution eventhough you should NOT HAVE ANY mold flying around in the air when you remove it from the old leather items.

c. Dry brush and vacuum removal- Be careful, many mold types arehazardoustoyourhealth.Wear protection. DO NOT BRUSH THE DRY MOLD OFF YOUR ITEM INTO THE AIR! It will spread to other areas of the room where it may grow later. If you have very little dry mold to brush off, then go outside and see which way the breeze is blowing (a small, clean, soft paint brush can be used). If you have a lot of dry mold to remove, get a vacuum cleaner with a HEPA filter, which will catch the mold spores and not spread them around through the exhaust. You may also be able to buy a HEPA filter and hold it over the suction hose of your vacuum cleaner. Use a brush nozzle and be careful of damaging (by sucking hard) or by scrapping the nozzle against the item. After you are done, throw away all used filters, masks etc!!! Don’t be penny wise and proud foolish and try to clean your mask, filters and gloves. Do what is best for your health.

Tip#7 The problem with giving you suggestions is that the old leather on a book binding is made different than a saddle, or a decorative panel in a piece of antique furniture. On top of that, deerskin is different than cow hide and so on with all the different kinds of skins. So, one set of instructions for cleaning and protective coating does not apply to all old leather heirlooms and collectibles. The very best tip I can give you is to give you 3 clickable links the Canadian Conservation Institute has written up with some directions for the general public and for collection care: N8/2 Care of Alum, Vegetable, and Mineral Tanned Leather, N8/3 Care of Mounted Specimens and Pelts, N8/4 Care of Rawhide and Semi-Tanned Leather

Professional art conservators and restorers that specialize in leather objects can confirm that leather is a very sensitive material. It could get affected by any solution you apply and change its colour or even worse, get damaged. If you follow the instructions of the CCI, always test solutions on a small part of the leather item, before you treat the whole surface. If you see changes in its appearance, do not hurry with the task. You can ask a professional objects conservator for advice. If you want to restore a valuable old leather possession, it is better not to do it on your own. Object conservators have special materials, equipment and expertise, which you probably do not possess. Do your research and find the best way to save your treasured items.

Here’s a useful extra Tip#8 – Sometimes we are accustomed to our surroundings (home or office) and don’t smell or see things like light mold infestation because we are so used to it. Having a cleaning company come to “back up” your cleaning efforts every once in awhile may allow some “fresh eyes” and a fresh nose to help you find problems. I’m sure the extra help will be well appreciated too. Perhaps they have a vacuum cleaner with a HEPA filter that will be very useful, as we have discussed in this article BUT, make sure they don’t clean mold off of old leather, artwork and collectibles with their commercial cleaning products and scrubbing techniques! Their techniques and products may be good for the sinks and floors but not for the collectibles, old books etc.

Many of these suggestions in this article were taken from the Save Your Stuff – Collection Care Tips multimedia e-book that you can download for free from It was written by a renown professional art conservator-restorer.

Water damage from a flood? No....

Water damage from a flood? No…. poor storage and completely avoidable.

If you would like to contact the art conservator/restorer and author of Save Your Stuff – Collection Care tips, Scott M. Haskins his email is 805 564 3438 (USA)

4 Responses to "Prevent and Remove Mold From Old Leather Belongings – 7 Useful Tips from a Preservation Expert"
  1. Really nice storage tips there. Perhaps one of the things that we all need to know especially if you love keeping records or some sort of historic artifacts, humidity is what you need to do away with. I have had to deal with molds before from some leather-ware and I wish I had seen this guide as it would have made my work a little easier. Thanks for the great share.


  2. ben day says:

    Thank you for your great article.

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