About RTS
Crafted by nature, perfected by precision, our slate delivers uncompromising strength and durability. Meticulously split from solid blocks, each piece boasts a smooth, fine grained surface with subtle longitudinal texture—naturally free from reactive minerals and fully compliant with BS EN 12326 (A1/S1/T1/W1 certified). Rigorous third-party testing confirms exceptional performance, even under extreme climatic stress.
Traceable Quality from Quarry to Roof Sourced exclusively from a single, trusted quarry and processed at our dedicated facility, every slate is palletized to the highest standards: shrink-wrapped, BS EN-certified, and traceability-coded for seamless logistics.
Nature’s Artistry, Built to Last
A testament to natural beauty, each slate features slight tonal variations in color and texture—most visible in sunlight. Over time, they develop a graceful patina, harmonizing with local weather conditions.
Pro Tips for Flawless Installation:
Quality Assurance: Cross-check shipments against our “Quick Quality Checklist” to guarantee premium-grade slate.
Aesthetic Balance: Blend slates from multiple pallets during installation to ensure uniform color distribution.
Request your BS EN 12326 Declaration of Performance today—where proven standards meet timeless craftsmanship.
1980 – 2026
Our Most Efficient Year
While modern machinery now handles heavy lifting and transport, Ankang’s slate industry remains deeply rooted in artisanal tradition.
The essence of our craft still lies in skilled hands – from precision splitting to meticulous quality control. This perfect balance of technology and craftsmanship ensures each piece maintains the timeless quality that has defined our region’s slate for generations.
Our History
Honoring Heritage Through Modern Craftsmanship
Chinese Slate Journey
1980
Chinese Slate Industries
The Chinese have been using slate for roofing for a long time. The slate companies were started in the 1980’s. The first export was through the China Mineral Import and Export Corporation to the USA and Europe.
1992
The Beginnings
Since 1992 many Chinese, German and Spanish companies have invested in the slate quarries in Shaanxi and Hubei Provinces. There were more than 100 small quarries in China.
Being a chartered quantity surveyor and consultant for Chinese overseas trade and investment. Fergus Liu was engaged by the local government for the natural slate development. He trained the quality control team to achieve the standards and requirements for different countries.
1997
Venture
China Slate Ltd formed a joint venture company and invested in the Dongmu quarry in 1997.
2008
Recession
In 2008, due to the world recession and the strict environmental control of the Chinese government, the slate quarries were closed one by one. Fergus Liu’s team kept the test results done by Dr. W from Germany of the slate quarries.
Partnership
In 2019, he teamed up with the slate quarry owners and the state owned companies to open up the best quarries. China Slate Limited has a team of geologists, mining and environmental engineers to develop good quality and sustainable slate quarries working closely with the Chinese local governments.
2019
Expansion
In 2025, with the assistance of the China Slate UK team, we established the Redtree Slate brand and decided to expand into markets other than the UK, aiming to make China Slate known to a wider global audience. Leveraging our own mines and standardized slate roof tile production capacity, we launched our global market expansion strategy.
2025
Why Choose RTS
6 Guarantees Behind Every Slate We Deliver
One Quarry
The production process
handled by one site
ensures all products from
this location.
Artisanally Crafted
Each piece is meticulously
handcrafted to preserve
natural slate textures.
Modular Customization
Mix and match modular
sizes to fit unique design
visions.
Full-process Control
Stone to finished product
– cutting, Edging, holing
, and packing within our
facilities.
BS EN 12326
BS EN 12326 CE
certified: A1/S1/T1/W1
compliant.
UK Warehouse
Standard-sized slate is
readily available and
stocked in ample quantities
across the UK.