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.
