Honister Green Slate, also known as Westmorland Green Slate or Lakeland Green Slate, has captivated hearts with its unique spectrum of colours, functionality and rich history for centuries. Formed deep underground within the boundaries of the beautiful Lake District National Park, mine activity has been taking place at Honister Slate Mine for almost 400 years with the first slate having been extracted in 1643.
Here at Honister Slate Mine, the last working slate mine in England, you can take a tour and see the remnants of century-old mine activity, take part in thrilling activities such as the Infinity Bridge or Via Ferrata and pay a visit to our gift shop where you will find a variety of quality slate products.
Situated at the top of Honister Pass in Borrowdale, no one else knows this landscape and its natural resources quite like we do. With our deep-rooted mining heritage, years of experience and highly skilled craftspeople on site, we know pretty much all there is to know about slate. From how slate is formed, why slate is so uniquely coloured and how to clean slate roof tiles, you’re in the right place to find out.
We’ve put together a list of our most frequently asked questions, or FAQs, and with all our expert knowledge answered them for you. So, if you’re interested in learning more about the formation of Honister Green Slate and its special characteristics, what it is used for, how to look after it and the fantastic products we manufacture with this incredibly versatile material… then read on!
What Is Slate?
Slate is a highly tactile fine-grained metaphoric rock, formed over millions of years due to the repetition of metamorphic rock layering when sedimentary materials are placed under enormous amounts of pressure.
For centuries, the rock has been extracted from slate quarries and utilised for a variety of purposes. Slate is a hardwearing, strong rock which can withstand a range of different weather conditions, making it a popular choice for both domestic and industrial purposes.
What Type of Rock Is Slate?
As mentioned above, slate is a type of metamorphic rock, meaning that it started as one type of rock (sedimentary rock) and – with heat, pressure and an enormous amount of time – changed into a different type of rock (metamorphic rock).
How Was Slate Formed?
Slate formation is a very slow process, taking millions of years to complete. The first step in the process of slate formation is the build-up of sedimentary rock, formed from the aggregation of sediments such as clay, silt, sand and volcanic ash.
Once the sediment has compacted together to form sedimentary rock, it undergoes a process called metamorphism. During this process, the sedimentary rock is subjected to high pressures and temperatures caused by the movement of tectonic plates.
The unique Westmorland Green Slate found at Honister Slate Mine has been dated at 450 million years old, where it has been pressed underground due to various conditions of the earth to form an elegant green coloured slate.
What Colour Is Slate?
Slate is commonly grey in colour however this varies depending on its mineral composition and where it is found. There are many different types of slate with varying natural colours including different hues of grey, purple, black, blue, green, heather and red.
Here at Honister Slate Mine, our Westmorland Green Slate is made up of volcanic ash that was spread across the land by erupting volcanoes millions of years ago. The magnificent slate colour of our Westmorland Green Slate comes from the magnesium chloride present in the ash.
What Is Slate Used For?
Due to its versatility, slate is popular for both domestic and commercial purposes. Some of the most common exterior uses of the rock include slate roofing tiles, slate chippings, slate house signs and slate outdoor seating. In the home, this type of rock is often used for slate kitchen worktops, slate flooring and slate hearths.
How Long Do Slate Roofs Last?
Slate roofing tiles can easily last 100 years and have been known to last far longer. If you’re moving into an older property that hasn’t had new roof tiles for decades, we recommend considering maintenance or an entire replacement and its always best to keep on top of replacing broken slate tiles as soon as possible however we recommend getting a professional to give their opinion beforehand.
How to Clean Slate?
While slate is very durable and requires little maintenance, from time to time you may feel that your slate roof tiles, slate hearths or other slate products would benefit from cleaning.
How to clean slate roof tiles?
You should first consider safety as you are not able to walk on slate roofs so the best way to approach it is with a long extension ladder. Next, remove any debris such as leaves and moss from your slate roof tiles. After this, you can begin gently scrubbing the slate with a medium-stiff brush and a mix of household cleaner and water. To remove the residual soap, gently spray your roof with a garden hosepipe. You should avoid using high pressure washers as these can break slate apart, particularly old or damaged tiles. If you are not comfortable giving this a go yourself its always best to call in a specialist, who will provide you with the best roof cleaning service.
How to clean slate hearth?
Thankfully, a slate hearth is much simpler to clean than slate roofing and polishing your slate hearth will ensure it looks as good as new. First wipe down the slate with a damp cloth to remove any dust or debris and leave to air dry before polishing. Next, apply a few drops of teak oil, WD40 or olive oil to a clean dry cloth and apply to the slate in small circular motions. Finally use another clean, dry cloth to buff out and absorb any excess oil.
What are slate gifts?
Slate gifts are beautifully hand-crafted items ranging anywhere from small decorations to large sculptures. No two pieces of slate are the same and it is a fantastic material to work with, making for truly unique gift-giving items.
The talented craftspeople at Honister Slate Mine are proud to produce a stunning range of slate gifts and keepsakes using our world famous Honister Green Slate. From slate homeware, artwork and keyrings, take home your very own piece of the Lake District from Honister Slate Mine Shop.
We hope this blog was helpful and if you have any further questions, don’t hesitate to get in touch with the friendly team here at Honister Slate Mine. Check out our unique range of slate gifts and products available at the Honister Slate Mine Shop.