cobble
Enable an agent to identify a cobble as a discrete rock clast, assess its condition and context, and determine suitable handling or use.
Bundle → Layer → Finding → Questions Filled
5 bundles · 9 layers · 15 findings · 23 questions
Clast identity and size Establish whether the referent is a rock clast and whether cobble is its supported size designation.
Referent and convention
Resolve the intended meaning and classification basis.
Cobble sense
Record evidence for interpreting the entry as a geological clast rather than another use of the word.
- Does the registry's upstream record identify a rock clast, a paving stone or a rolling-process cobble? definition
- Which size classification and boundary convention should govern this model? boundary
Dimensional assessment
Relate measured clast dimensions to the selected class.
Size assignment
Preserve the measurement method and uncertainty behind a cobble designation.
- What are the three principal axis lengths, and were they measured directly or estimated from an image? measurement
- Does the governing axis or sieve measure fall within the chosen cobble interval, including measurement uncertainty? boundary
Rock fabric and integrity Describe the material and weaknesses of the individual clast.
Lithology and fabric
Capture observable rock composition and internal structure.
Material identification
Distinguish observed mineral and fabric evidence from an unverified rock-type label.
- What visible grains, crystals, pores, bedding or foliation support the proposed lithology? definition
- Was the identification made from the exposed surface, an existing fresh face or an analytical test? provenance
Fractures and weathering
Assess existing damage and deterioration without assuming that an intact outline means sound rock.
Integrity observations
Record cracks, weak planes, loose material and differences between rind and interior.
- Where are visible cracks, separations, friable patches or loose flakes, and how extensive are they? measurement
- What observed weaknesses require support or further assessment before lifting, cleaning or loading the cobble? action
Form, surface and contact Describe clast geometry and the surfaces that govern contact with hands, supports and neighbouring stones.
Shape and edge form
Assess overall proportions independently from edge rounding.
Shape description
Record whether the clast is elongated, flattened or equant and how rounded its edges are.
- What axis ratios describe the cobble's elongation and flattening? measurement
- Which roundness scale was used, and do fresh broken edges differ from the rest of the surface? measurement
Surface and seating
Describe coatings, roughness and observed support behaviour.
Contact condition
Assess how particular faces and surface deposits affect handling and placement.
- Which faces carry mud, polish, biological growth or other coatings, and under what moisture condition were they observed? measurement
- In the proposed support or bedding, which orientation seats the cobble securely and which orientations rock or roll? action
Occurrence, modification and use Connect the clast to its observed setting, movement history and proposed treatment.
Setting and history
Preserve observed occurrence and distinguish it from inferred transport history.
Contextual evidence
Record the host setting, collection history and evidence of working without inferring origin from roundness alone.
- Where and in what deposit or constructed setting was the cobble observed, and was its position recorded before movement? provenance
- What evidence supports natural abrasion, deliberate working or reuse, and which interpretations remain uncertain? provenance
Treatment and fitness
Evaluate a concrete proposed action against the clast's condition and contextual value.
Use-specific decision
Require evidence appropriate to the intended use rather than treating cobble classification as proof of suitability.
- For the proposed use, which requirements for dimensions, durability, surface behaviour or cleanliness need verification? action
- Would collection, washing, splitting or placement remove features or context that should first be documented or assessed? action
Evidence and external alignment What the world already says about this thing, gathered so the model can be checked against it.
Reported evidence
Findings from the breadth pass, kept separate from the structural claims.
Check these first
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these check these first hold for the sense of cobble this model covers, and on what evidence? provenance
Kinds and varieties
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these kinds and varieties hold for the sense of cobble this model covers, and on what evidence? provenance
Real-world use
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these real-world use hold for the sense of cobble this model covers, and on what evidence? provenance
Typical measurements
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these typical measurements hold for the sense of cobble this model covers, and on what evidence? provenance
Failure modes and hazards
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these failure modes and hazards hold for the sense of cobble this model covers, and on what evidence? provenance
Regional variation
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these regional variation hold for the sense of cobble this model covers, and on what evidence? provenance
Neighbouring kinds and how to tell them apart
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these neighbouring kinds and how to tell them apart hold for the sense of cobble this model covers, and on what evidence? provenance
Classifiers Filled
- Family
- Thing Registry
- Category
- Physical world and living systems
- Entry kind
- thing
- Plane
- PHY
- Domain
- PHY.OBJ
- Other names and narrower kinds
- Otá
What it is Filled
A cobble is a rock fragment in the sediment-size class between pebble and boulder, conventionally 64-256 mm in diameter on the Udden-Wentworth scale, irrespective of its composition or roundness.
In scope
- Identification of an individual rock fragment as cobble-sized under an explicitly named classification
- Clast dimensions, shape, angularity and surface texture
- Rock composition, weathering, fractures and attached material
- Natural occurrence, collection history and subsequent modification
- Suitability for a specified handling, sampling or construction action
Out of scope
- A sediment deposit or aggregate batch containing many clasts
- The rock type or mineral species considered independently of an individual clast
- An entire cobblestone pavement or other constructed assembly
- A deliberately manufactured paving unit classified principally by its product specification
- A cobble meaning tangled or misdirected metal in a rolling process
Why it exists Filled
Enable an agent to identify a cobble as a discrete rock clast, assess its condition and context, and determine suitable handling or use.
Distinguishing features Filled
- Assign cobble status from measured dimensions and a named size classification; a rounded appearance alone does not establish the class.
- Distinguish cobble from pebble and boulder using the selected classification's boundaries and measurement convention.
- Record angularity separately from size so that the everyday association with rounded stones does not silently become an identification requirement.
- Distinguish a natural clast selected for paving from a cut or manufactured paving unit by examining worked faces and production history.
- Confirm that the referent is a discrete rock fragment rather than a sediment mixture, continuous bedrock or a rolling-process event.
What robots and AI may and may not do Filled
Must not
- Remove cobbles from protected beaches, riverbeds or archaeological sites.
- Confuse the sediment size class with cobblestones used for paving.
- Report a size class without stating the scale used.
Only with a human decision
- Extracting cobbles from rivers or beaches where it may harm habitats or coastal protection.
May
- Classify a rock fragment as a cobble by its measured size under a stated scale.
- Describe cobbles in sediment or soil logs.
Moral aspects Filled
- Removing cobbles can destroy fish spawning beds and coastal defences.
- Classification consistency matters for engineering and science.
Who is affected
- River and coastal ecosystems
- Coastal communities
- Engineers and geologists
Owners Filled
Steward
Nobody owns the size class; landowners or the state hold the material in place.
Links to other meta-models Filled
parent
- Q100384264 - registry parent class
What else AI and robots need to interact with it Filled
Identity and identifiers required Filled
- Vercy registry: vr.tr.cobble
- Wikidata: Q1527595 (https://www.wikidata.org/wiki/Q1527595)
Direct properties required Filled
- Classification basis: Named size classification, version and boundary convention; unresolved
- Principal dimensions: Longest, intermediate and shortest axes in mm, with method and uncertainty
- Classification result: Cobble under selected convention; boundary case; outside class; unmeasured
- Roundness and angularity: Named visual scale and assigned class; unassessed
- Overall form: Equant; flattened; elongated; irregular; assessed using a stated method
- Rock identification: Observed lithology and constituent minerals, with identification confidence; unknown
- Mass: kg, with wet or dry condition stated
- Surface and fracture condition: Observed cracks, loose fragments, weathered rind, coatings and biological growth
- Occurrence and provenance: Links to observed location, host deposit, collection event and later custody
- Human modification: No modification observed; cut; split; drilled; polished; other observed working; uncertain
Recognition required Filled
- A rock fragment larger than a fist and smaller than a boulder, roughly 64 to 256 mm across.
- Often rounded by water on beaches and in riverbeds, but shape is not part of the definition.
Capabilities and actions required Filled
- Measure and classify the clast using a declared size convention.
- Inspect and document rock type, form, fractures and surface features.
- Compare candidate cobbles for a specified placement or aggregate requirement.
- Record the original setting before collecting or relocating the clast.
- Select handling and cleaning methods based on mass, instability and evidence to preserve.
- Refer suspected worked or scientifically significant specimens for assessment before alteration.
Hazards and failure modes required Filled
- Different scales use slightly different size limits, causing classification errors.
- Removal from shores and rivers increases erosion.
Standards and interfaces required Filled
- ISO 14688-1 Geotechnical investigation and testing, identification and classification of soil, International Organization for Standardization.
Context of use required Filled
- Cobbles occur in river channels, beaches, glacial deposits and other settings where coarse rock fragments accumulate.
- Geologists record them when describing sediment size, transport processes and depositional environments.
- People also use suitably selected cobbles in landscaping, paving and erosion protection.
Sources Filled
- Wikidata item Q1527595: cobble - identity and sense of the item
- Wikipedia: Cobble (geology) - general description of the item
Open questions
- Does vr.tr.cobble denote a geological size class, a paving stone or a metal-rolling occurrence? The supplied registry context does not settle this.
- Which authoritative size classification, numerical limits and measurement convention should define cobble for this catalogue?
- Does an existing Vercy world model already own this concept, requiring a registry link instead of a separate publication?
- Where should the catalogue draw the boundary between a natural cobble selected for paving and a worked paving unit?
- Which use-specific sources and assessment methods are needed before this model can support construction suitability decisions?
Machine files
Provenance
thing registry research (pass 2) · unreviewed
Built from: models/things/publications/thing-q1527595/spec.json