Quartz Wars: Green Scorecards for Cambria, Caesarstone, Silestone, MSI
Engineered-stone makers all promise planet-friendly slabs, but the data behind the slogans tell a messier story. We combed through the newest EPDs, VOC labels, and sourcing claims for four market leaders so specifiers can see who’s really walking the talk.
Embodied carbon: count the kilos, not the hashtags
Caesarstone is the lone brand with a 2024 EPD that meets EN 15804 +A2. Its Mineral-collection slabs average 1.42 kg CO₂-eq per kg at A1–A3, roughly 35 kg CO₂-eq per square metre for a 25 kg/m² slab (Caesarstone EPD, 2024). Silestone’s older but still valid EPD shows 44.7 kg CO₂-eq per m² for a comparable 10 mm product, about 20 % higher (International EPD System, 2023). Cambria and MSI have no published EPDs at all, so buyers must lean on generic database values that hover near 45–50 kg CO₂-eq per m² for quartz composites (NMD, 2025). In carbon terms, Caesarstone is currently the low-number leader.
VOCs: breathing room matters
All four brands advertise GREENGUARD Gold certificates for finished slabs, signaling very low indoor emissions. Cambria goes further with a Health Product Declaration and Declare label that list every ingredient (Cambria LEED FAQ, 2024). Caesarstone and Silestone publish similar Declare labels, while MSI cites only the GREENGUARD report (MSI Environmental Commitment, 2025). On VOCs, the playing field is tight; transparency sets the real gap.
Sourcing storylines: miles and minerals
Cambria quarries most quartz in North America and manufactures in Minnesota, trimming freight emissions and simplifying traceability. Caesarstone ships raw minerals from Turkey, China, Portugal and others to its Israeli plant (Caesarstone EPD, 2024). Silestone’s production sits in Spain with a public pledge to run on 100 % renewable electricity (Cosentino HybriQ release, 2022). MSI aggregates supply from 25+ factories worldwide, mixing domestic and imported slabs. The shorter the supply chain, the easier audits become.
Data gaps: silence is still a signal
Lack of an EPD is not illegal, but it blocks project teams chasing LEED v5 or public Buy-Clean tenders. Cambria’s and MSI’s silence forces architects to assume conservative default factors, which can knock a countertop out of a tight carbon budget. That’s money left on the shelf, literaly.
So which quartz is “green”?
Today’s scoreboard crowns Caesarstone for embodied carbon and Cambria for ingredient disclosure. Silestone lands in the solid middle thanks to decent carbon numbers and renewable-energy claims. MSI falls to the back, hampered by scant third-party data. The rankings could flip fast once new EPDs appear, but until then, specifiers who need hard proof may find their choices already made.
Frequently Asked Questions
Can we use Cambria on a LEED v5 project without an EPD?
Yes, but the LEED credit for product-specific carbon data would be lost; teams must apply a conservative default impact factor instead, which can raise the project’s calculated footprint.
Does Caesarstone’s low carbon figure include end-of-life recycling?
No. The 1.42 kg CO₂-eq per kg covers stages A1–A3 only. End-of-life adds another ~0.12 kg CO₂-eq per kg, still keeping total below 2 kg CO₂-eq (Caesarstone EPD, 2024).
Is Silestone’s 2019 EPD still valid after PCR updates?
Yes. The document remains valid until January 30 2027, but the next renewal will need the newer EN 15804 +A2 PCR version.
Do MSI slabs off-gas formaldehyde?
MSI’s GREENGUARD Gold certificate confirms emissions below 0.0073 ppm, well under the California 01350 limit, so formaldehyde is not a concern (MSI Environmental Commitment, 2025).
About the Author
Eric works at the intersection of sustainability, regulation, and business strategy, helping manufacturers navigate the evolving landscape of EPDs and LCAs. Having spoken with hundreds of teams across North America, brings a deep understanding of what drives ROI, what regulators are asking for, and how companies can stay ahead with smart, scalable approaches to environmental reporting.
