Where does slate come from?

The process of producing our quality slate chippings all begins in the stunning Welsh countryside. Our slate is sourced from 2 different quarries in Wales - Bethesda and Ffestiniog. These sites have been producing slate for hundreds of years.  

The graphite grey slate is extracted from the mountains of slate that was mined many years ago and considered as waste by the companies who mined it to manufacture roof tiles.

Click here for more information on the history of Welsh slate.

Grey Slate Chippings

How are slate chippings produced?

Heavy state of the art plant machinery is used to dig into large piles of slate and tip huge loads into a crusher. The crusher breaks down and separates the slate chippings into specific sizes and gradients. Each size is then transported to our custom built plant in Port Penrhyn, Wales, and placed into large storage bays ready for bagging.

Slate Chipping Crusher

Our dedicated team of plant workers processes all materials through several bagging plants. Various sizes are available - most commonly, bulk bags of approximately 850kg and maxi bags of approximately 25kg. Empty bags are positioned beneath hoppers where they are filled with material. Bulk bags are positioned onto a pallet before being filled and taken to our storage area, ready for ordering. Individual 25kg maxi bags are neatly stacked onto a pallet by a robotic arm and wrapped for added protection.

Real Welsh Slate from Decorative Aggregates is sourced from the slate landscape of Northwest Wales which is recognised as a UNESCO World Heritage site and which historically has supported local economies and has been the centre of many communities.

To ensure the natural beauty of the slate is maintained, we do not handle the material or process it more than is required. Slate chippings may occasionally arrive with a natural grey coloured dust covering.

We advise you allow the slate time to be rinsed by natural rainfall or, if you cannot wait to see the beautifully natural slate colours, the slate can be washed using a hosepipe.

Slate chippings will generally take a few weeks to allow the true colour to show. Please see the images below which highlight the difference between washed and unwashed slate.

Slate chippings - washed vs unwashed

Blue Slate Chippings

Blue Slate Chippings 40mm Washed vs Unwashed

Graphite Grey Slate Chippings

Graphite Grey Slate Chippings 40mm Washed vs Unwashed

Plum Slate Chippings

Plum Slate Chippings 40mm Washed vs Unwashed

Where do slate monolith's come from?


Our striking Slate Monoliths come from Ffestiniog in Wales and are picked from the same source of slate used to create our slate chippings. When a slate piece of substantial size is identified, it is set aside to become a monolith rather than being loaded for chippings.

All monoliths are cut to create a flat base and measured and stored based on their height.

They are transported to Port Penrhyn where the team identifies their final usage. Undrilled Monoliths are stored immediately. Drilled Monoliths are placed on a drilling machine where a 32mm hole is cut from top to bottom so they can be used as a water feature. Slate Holloliths are produced in the same manner however the team also cuts out a large circular hole through the face of the monolith.

How are Slate Planters, Walling and Rockery made?

Grey Slate Rockery

The production of Slate Rockery, Walling and Planters is a very manual and rigorous process. The team at Port Penrhyn has years of experience in handpicking and choosing only the highest quality slate pieces for use in gardens and landscapes.

Slate RockerySlate Walling and Slate Planters arrive as full loads of slate that have been screened to a certain size.

The team handpicks suitably flat pieces of a similar size to be placed into baskets and supplied as Slate Walling. 

Slate pieces are hand selected by the team to be drilled and supplied as Slate Planters. The team looks for pieces which are the correct shape and whose grain runs in the correct direction for drilling.

The remaining material is checked for quality and packed to be sold as Slate Rockery

Did you know: You can identify exactly where a piece of slate comes from just by looking at the grain.

The production of Slate Rockery, Walling and Planters is a very manual and rigorous process. From years of experience, the team at Port Penrhyn handpicks only the highest quality slate pieces to use in gardens and landscapes.

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