Each quarried family brings a different balance of look, durability, and price:

1. Sandstone is the volume favourite: warm buff, brown, grey, and multicoloured blends, a naturally riven grip surface, easy cutting, and the friendliest price of the four. It suits traditional gardens and takes decades of pedestrian wear; its openness to water makes sealing worthwhile in shaded, mossy plots.
2. Limestone reads calmer — tight, even grain in blue-black, grey, and cream, with a subtly textured face that suits both cottage and modern schemes. Slightly denser than most sandstone, but avoid it where acid exposure is likely (some cleaners etch it).
3. Granite is the engineering choice: extremely hard, almost non-absorbent, happy under driveways in setts or flamed slabs, and crisp in contemporary silver-grey and black. It costs more to buy and to cut, and its formality suits architectural gardens more than rambling ones.
4. Slate delivers the deepest colours — charcoal, blue-grey, rustic copper — in a fine layered texture. Quality varies by origin more than any other stone: dense paving-grade slate wears beautifully, while soft grades can delaminate in hard frost, so buy paving-specified slate only.

The honest cross-check for any choice: view wet samples (stone transforms when rain darkens it), confirm the stone is sold as calibrated (even thickness) unless you enjoy bedding roulette, and ask for the specific quarry's slip and absorption figures rather than the family reputation.

The finish describes how the face left the works, and it sets both the look and the laying:

Riven stone is split along its natural bedding planes, keeping the undulating, cleft face the quarry gave it. This is the traditional look — every slab a slightly different relief — and the texture doubles as slip resistance. Hand-riven sandstone and slate carry the strongest character; the trade-offs are variable thickness in uncalibrated grades (slower laying on a full bed) and a surface that holds a little more dirt in its hollows.

Sawn (and honed) stone is cut flat on diamond saws and often lightly smoothed, producing crisp, even faces and square edges — the contemporary terrace aesthetic. Sawn faces show the stone's figure like polished furniture shows grain, lay quickly at consistent thickness, and sweep clean easily. Being smoother, they earn their outdoor grip from a secondary texturing — shot-blasting, flaming (granite), or brushing — which good suppliers apply as standard on external sawn ranges; verify the slip rating rather than assuming.

Between the poles sit tumbled (softened edges, aged look) and brushed (gentle sheen with grip) finishes.

Selection is mostly architectural honesty: riven belongs with cottage planting, reclaimed brick, and rolling levels; sawn belongs with rendered walls, straight lines, and porcelain-adjacent minimalism. Underfoot performance is equal when each carries its appropriate texture — the choice is the story the garden tells.

Stone forgives more than porcelain but rewards the same discipline:

1. Base: excavate to firm ground and build a compacted MOT Type 1 (crushed aggregate) sub-base of at least 100 mm for patios — more for gateways and any vehicle touch. Weak, unconsolidated bases are behind almost every rocking, cracked stone patio.
2. Bed: lay on a full wet mortar bed of 30–50 mm (roughly 6:1 sharp sand:cement for absorbent stones, stronger for granite) — never the five-spot dab method, which leaves hollow slabs that crack under point loads and show reflective staining. Uncalibrated riven stone needs its bed adjusted slab by slab.
3. Priming: granite, slate, and some dense sandstones benefit from an SBR/slurry primer on the underside for adhesion; absorbent sandstone generally bonds directly but should be laid damp-backed, not bone-dry, in hot weather.
4. Joints and falls: 8–15 mm joints for riven stone (5–10 for sawn), pointed with mortar or a stone-compatible brush-in compound; falls of ~1:80 away from the house; movement respected at large terraces' edges.
5. The stain rules: wash mortar smears off immediately (cement stains absorbent stone permanently), never use acid cleaners on limestone or many sandstones, and shuffle slabs from at least three packs while laying so quarry colour drift blends across the patio rather than banding.

Done this way, the maintenance question becomes cosmetic rather than structural for a generation.

Sealing is a choice, not a requirement — stone paved footpaths predate sealants by some centuries — but the right sealer buys convenience on absorbent stones.

The case-by-case answer: porous sandstones and limestones in leafy, shaded, or high-traffic settings benefit most: an impregnating (breathable) sealer slows water uptake, so moss, algae, and tannin stains from overhanging trees stay on the surface and wash off. Dense granite and quality slate absorb so little that sealing adds mainly peace of mind. If sealing, use impregnators, not film-forming 'wet look' coatings, which peel and yellow outdoors; seal only after the stone has fully dried post-installation and efflorescence has finished; and expect to refresh every 3–5 years.

Routine maintenance, sealed or not: sweep regularly (organic debris is what feeds staining), wash seasonally with warm water and a pH-neutral or stone-specific cleaner, and treat green growth with a stone-safe algaecide rather than aggressive bleaching. Pressure washing is the tool to ration: an annual moderate wash is fine on sound stone, but frequent high-pressure passes strip riven faces, open the grain, and blast out pointing — much 'worn out' stone is actually pressure-washed-out.

Stain triage: rust from furniture responds to stone-specific rust removers (never acid on limestone); oil to poultice cleaners; cement haze to careful specialist products. And keep the golden habit — spare slabs from the original batch in the shed — because the day one slab must be replaced, matching weathered stone from a new quarry lot is otherwise pure luck.

Stone's slip behaviour is finish-driven, so safety is a specification question rather than a material verdict.

Textured finishes grip well wet: riven sandstone and slate, flamed granite, and shot-blasted sawn faces typically test in the low-slip range wet (PTV 36+ / R11-equivalent) — these are the finishes centuries of wet courtyards were built from. Smooth finishes do not: honed and polished stone becomes genuinely hazardous wet and belongs indoors or under cover. The specification rule for outside: buy external ranges with published wet slip values and choose texture first, colour second, at every wet-duty location.

Pools: granite, dense sandstone, and paving-grade slate all serve around pools with the right texture and a barefoot-comfortable surface; limestone needs care with chlorinated splash (chemical etching) and soft slates are excluded. Copings want rounded, textured nosings from the same stone range. One climate note: dark stones heat strongly in full summer sun — barefoot comfort favours mid-tones in hot regions.

Steps: stone steps are wonderful and unforgiving — specify full-depth treads with a textured finish, a visible nosing (contrast band or tooled groove where visibility matters), falls that shed water off the tread, and absolutely no smooth-honed faces. In frost climates, texture matters double: a filmed-over smooth step in the first November frost is the classic garden accident.

Kept clean — because algae defeats any texture — properly specified stone is among the safest outdoor surfaces there is; its long service on harbour sides and market squares is the field evidence.

Pedestrian paving: calibrated natural stone for patios runs 22–30 mm (sandstone and limestone commonly ~25 mm, slate 20–25, granite 20–30). At these thicknesses on a proper full mortar bed over compacted sub-base, foot traffic, furniture, and planters are trivial loads. Uncalibrated riven stone can vary 20–40 mm within a pack — charming, and slower to lay.

Vehicles change everything. A car's point loads flex thin slabs into cracks regardless of stone strength; vehicular stone paving means 40–60 mm slabs (or setts/cobbles at 50–100 mm) on an engineered base — typically 150–200 mm compacted sub-base or a reinforced concrete slab with a bound bedding layer, plus mortared joints and solid edge restraints. Granite dominates stone driveways for good reason: its hardness resists tyre scrubbing at gateways where cars turn. Sandstone drives exist but need the thickness, the base, and acceptance of faster surface wear at steering points.

The judgement calls: the occasional-crossing case (bins, a delivery van once a year) still deserves the vehicular build-up along the crossing strip — 'it's only occasional' is the origin story of most cracked gateways. Ramps and thresholds where wheels brake or turn concentrate loads further and favour setts over slabs. And whatever the duty, thickness is the cheap variable: upgrading slab thickness costs far less than excavating a failed drive — specify for the heaviest wheel that will ever cross, not the average one.

The garden design world's standing debate, honestly scored:

Choose natural stone for authenticity and ageing: no print repeat, geological depth of figure, and a weathering curve that adds character — lichen on sandstone and softened riven edges read as garden maturity, not decay. Stone is also kinder to cut intricately, repairs invisibly from the spare pack, and at the sandstone end undercuts porcelain on price. Its account book: absorbency (sealing and stain care on the porous families), quarry variation to manage while laying, and colour that shifts with wet and season — which is either its charm or its inconsistency, depending on the beholder.

Choose porcelain for a locked-in look and minimal upkeep: colour that never fades, zero sealing, wine-and-oil immunity, and factory-exact sizing that lays into crisp minimal joints. Its account book: printed faces repeat if the range is cheap, cut edges show the body colour, installation is less forgiving (priming, diamond cutting), and mid-range porcelain costs more than mid-range sandstone.

The deciding questions in practice: How will it be maintained (honestly)? Low-attention households lean porcelain. What is the architecture — period and cottage settings flatter stone; sharp contemporary lines flatter either, with porcelain giving tighter joints. Is barefoot pool use central? Both work; porcelain's rated textures make specification simpler. Many strong designs now mix them — stone at the garden's heart, porcelain on the high-maintenance dining terrace — which is less a compromise than an admission that the two materials solve different halves of the same brief.