The Ultimate Reference Guide to Cork Material
Do you worry about climate change and worry about how your consumer choices affect nature? Do you wish that there were more eco-friendly options? Do you want to know if cork material is a good, eco-friendly option?
If your answer to any of these questions is yes, then you are in the right place! Keep reading to learn all about the amazing cork oak tree, cork material and its innumerable properties. It is a wonderful option for all those who love nature and want to contribute to making our environment better.
In today’s world, we’ve unfortunately already done substantial damage to our environment. So, it’s good to look at products that are created out of any kind of eco-friendly material. Be it a handbag, wallet, footwear, jewellery, cell phone case or a musical instrument, if it is made using an eco-friendly material, it helps reduce our negative impact on the environment. Cork material is an eco-friendly, sustainable product that can be used to create hundreds of different items. Read this complete article to learn all about cork material and its benefits.
What is Cork?
Cork is simply the bark of a cork oak tree. This tree is unique and evergreen in nature. Cork is the thick and dark grey bark of the tree. Cork oak is unique because it has the ability to regenerate its outer bark. Once a cork tree is 25 years old, it can be stripped of its cork once every 9 to 12 years. This means that a single cork oak tree, which has an average lifespan of 200-300 years, can be harvested more than 16 times. Better yet, all of this can be done without any harm to the tree. It is believed that each tree can produce enough cork material for around 4000 wine corks.
Where do cork oak trees grow?
Cork trees grow mainly in the Mediterranean region. This part of the world produces more than 80% of the world’s total cork production. Countries that receive a lot of sunshine, low rainfall and high humidity have a lot of cork oak trees. Portugal is considered to be the home to the largest collection of cork oak trees. Other countries that produce cork are Algeria, Spain, Morocco, France, Italy and Tunisia.
What’s the origin of the cork tree?
References of cork trees and their uses in history go back thousands of years ago. History has many stories regarding cork material and cork applications. It is believed that in China cork material was used in 3000 BC for the purpose of fishing. Similarly, Egypt, Babylon and Persia also used cork material to produce various everyday items. In Italy, articles such as floats, stoppers for casks, women’s footwear and roofing materials made of cork date back to 4th century BC.
For thousands of years, cork has been used as a stopper in bottles. But did you know that cork was even found in the tombs dating back to primitive Egypt? Not only this, but ancient Greeks and Romans also made good use of cork material. They used it to make fishing nets, sandals, wine bottle stoppers and even personal flotation devices for fishermen. Villagers used it to build homes as it kept their houses warm in winters and cool in summers. In addition to this, cork made the floors soft and comfortable to walk on.
How is Cork Made?
The cork oak tree grows thick layers of bark. These layers are stripped off the tree to get cork. It is then boiled and pressed to make it more elastic.
The process of cork tree harvesting happens between the months of early May to late August. It is important to note that skilled cork harvesters known as extractors carry out the activity with their hands and no mechanical stripping devices are used for this purpose. These experienced cork extractors use a specialized cork axe to split the outer bark and peel it away from the tree. Vertical and horizontal cuts are made through the bark. All this is done carefully so as not to hurt the living part of the tree. It is usually done on the trunk, however, in case the tree is large, the lower branches are also used. The layer is then removed using the wedge-shaped side of the hatchet. Overall, cork tree harvesting is done very carefully and gently.
Turning Cork into Cork Leather
Though the process of converting cork into cork leather seems simple, it is not that easy. After cork is harvested, the planks of cork are stacked and left to dry. This is done in order to improve the quality of cork material. The planks stay stacked for a considerable period of time ranging from a few weeks to six months. This air-drying process helps the planks lose a lot of moisture and become flattened. Next, these planks are treated with heat and water so that all the dirt and tannins are removed. This makes the cork softer and flexible. After this, the poor-quality outer layer of the cork is scrapped off. Once again, the planks are then stacked and allowed to dry for a few more weeks. Finally, to give a uniform look, the cork is trimmed. It is then sorted based on its quality. The finest cork is used to create products like wine bottle stoppers while the inferior cork is used to make other products.
Leftover Cork Uses
The best thing about the cork harvesting process is that it’s completely environmentally friendly. Any waste that is generated during the process is reused and nothing goes waste. The leftover cork powder is collected and used as fuel in the factory. Small pieces of cork are made into chipboard. Chemical by products such as tannins (used for curing leather), hard wax (used in products like paraffin, paint, and soap), and phonic acid (used to make plastics and musk-scented toiletries) are all used by various industries.
What are the Properties of Cork?
Cork is a perfect masterpiece of nature. Cork is eco-friendly, renewable, sustainable, water resistant, natural and much more. The list goes on and on. In fact, cork is believed to be one of the most versatile materials on Earth. Let’s look at some of the reasons why cork material is so incredible.
Elastic - The membrane of the cork cell is extremely flexible, compressible and elastic. This is why cork material returns to its original shape even when a lot of pressure is applied to it. Also, it is because of its elasticity that cork is widely used for bottle stoppers. Even after years of compression in the neck of a bottle, cork is able to retain its elasticity and maintain an airtight seal.
Impermeable or Water Resistant - A waxy, rubbery substance called suberin is present in cork cells. This substance is extremely hydrophobic, which means that it strongly repels water. Because of suberin, water is unable to enter into the cells of the cork bark, thus making cork products completely water resistant. This also prevents any growth of mould, mildew, or moisture, which in turn makes cork material and products made of cork hypoallergenic.
Fire Retardant - These days there is a lot of discussion about wildfires or forest fires that are often uncontrollable and dangerous. Surprisingly, cork oak trees act as a protective force against such wildfires. This is because cork is fire resistant. This means that it does not catch fire even when it comes in contact with high temperatures. If cork does happen to catch on fire, it does not produce flames. and Instead, it releases a non-toxic smoke when burning.
Durable - Cork material is extremely durable. Be it a wallet or a piece of jewelry, if it is made using cork material, it’s sure to last for a very long time. Cork material ages extremely well, and doesn’t lose its durability over time.
Lightweight - Cork material is extremely lightweight. For reference, it’s 5 times lighter than water. Cork has low density and so it always floats on water. This makes cork material useful for fishing nets and life vests.
Sound Insulator - There is gas between the cells of cork material. Because of this gas, cork has a low conductivity of noise and vibration. This makes it perfect for use in greenhouses, floors, walls, and any type of soundproofing applications.
Cork Applications & Uses
As cork material has innumerable properties, it's a perfect choice for various products across different industries. Here are some of the most popular cork applications:
Cork is also used to create wall tiles. These tiles look quite pleasing to the eyes and they also provide heat insulation and absorb sound. In addition to this, they are also highly scratch resistant. Because of this, they are often used on public buildings like schools, government offices, and hospitals. Their distinctive look and durability make them perfect for such places.
Benefits of Cork Material
Cork material has many benefits, the most important being that it is eco-friendly and does not harm nature. In fact, cork trees help nature thrive and harvesting cork bark is an important part of the process.
Eco-friendly - Cork oak trees remove a huge amount of carbon dioxide from the atmosphere. Because of this, the cork forests are considered to be carbon sinks. They absorb nearly 14 million tons of carbon dioxide every year during their natural regeneration. Harvesting the bark from the tree aids in the regeneration process, and helps the tree absorb more carbon dioxide and release more oxygen.
Anti-Pollution - Cork never pollutes the environment. Only the bottom part of the cork tree is harvested.The rest of the tree is unaffected and it keeps providing fresh air.
Best Alternative to Leather and Plastic - Cork is 3 times lighter than traditional leather but just as durable. It’s also attractive, water resistant, and full of naturally occuring amazing properties. Cork is becoming more popular as an alternative to animal leather or plastic.
- Protection for Endangered Animals - Acorns, the fruit of the oak tree, are food to several endangered animal species. These trees are also excellent habitats to wildlife, some of which, like the Iberian lynx, are in danger of extinction. It’s not only animals that need cork trees for protection, many rare species of plants and fungi also find a home among these trees.
How Long Does Cork Last?
Cork oak trees live for almost 200-300 years. Additionally, the products created out of cork material last for a very long time. The durability of cork products is usually greater than those made of leather or plastic.
Is cork 100% recyclable?
Yes, cork is 100% recyclable. Cork of different ages is used to create different products. In other words, no cork is ever wasted. Young cork is good for flooring, insulation, and sustainable fashion while old cork works best for wine stoppers. Even after its first usage, cork can be grinded into pieces to create new items.
Is cork a sustainable material?
Yes, cork is a sustainable material because the cork tree is not cut down to obtain cork. It is only the bark that is stripped to harvest the cork. The tree continues to live and grow. In fact, cork’s sustainability and easy recycling of its products are two of its most distinctive features.
Is cork expensive?
Yes, cork is much more expensive as compared to its other alternatives. The reason is because it’s naturally harvested only once a year by skilled workers.
What temperature and soil conditions do cork trees need?
To grow well, cork oak trees need a sandy, chalk-free soil with low nitrogen and high potassium. They also need rainfall from 400-800 mm per year and a temperature range between -5 ºC to 40 ºC.
It is amazing that in today’s synthetic world where nothing seems to be natural, cork is such a wonderful product. It does so much for us without harming nature in any manner. The range of products created out of cork material is wide. With new ways to use it being thought of all the time, it’s definitely going to be an environmentally friendly favorite for many years to come.
However, with all this said, there is always a significant difference between reading about something and actually feeling that material. Cork and its products also need to be touched to truly understand how amazing it is. We hope you can experience it someday to sense and appreciate this wonderful creation!