Core sample quality records connect observations with the drilling interval, measurement context and unresolved issues. Before mobilization, agree the fields, definitions, responsibilities and correction process so receiving teams can understand the evidence without mistaking a complete-looking record for a guaranteed recovery result.
Table of Contents
Before the first shift: define what the record means
When defining core sample quality records, separate three things: the identity of the sample, observations about the recovered material, and any interpretation made from those observations. They need to remain linked, but they should not be recorded as if they were the same statement.
A hole and run reference provides context. A measured recovered length is an observation under a stated method. A conclusion about missing material or suitability for a particular use requires its own evidence and responsible reviewer. A complete set of identification fields does not establish that every quality requirement has been met.
Start with the geology team’s approved plan. Identify which measurements and descriptions are required, what terminology means and who is qualified to record or review each item. Where a defined index or method is used, retain its applicable reference. Do not create a project acceptance threshold from a general equipment article.
For reporting under the JORC Code 2012, Table 1, sample-recovery assessment and logging are explicit reporting topics. Use the reporting framework applicable to the project; this reference does not set a universal recovery acceptance threshold or establish compliance for any particular sample record.
| Field group | Purpose | Definition to settle |
|---|---|---|
| Hole and run reference | Connect the record to its source | Approved identifiers and how they relate to other project records |
| Drilled interval | Describe the actual work interval | Reference convention, units and source of start/end information |
| Recovered material | Preserve the agreed measurement and description | Measurement method, condition terms and recorder |
| Relevant configuration or change | Explain the equipment context | Which changes need reference to the actual configuration record |
| Exception | Keep an unresolved issue visible | Status, evidence, reviewer and route to a decision |
| Review history | Explain how the record became accepted or corrected | Who reviewed it, when and under which document version |
This is a planning aid, not a replacement for an approved field form. Remove fields that do not serve the project and add those required by its actual methods. Define the meaning before requiring everyone to fill the box.
Make a missing value distinguishable from a measured result
In core sample quality records, an empty field can mean several things: not measured, not applicable, unavailable, awaiting review or simply overlooked. None automatically means zero. Agree how the relevant states will be recorded so the receiver does not need to guess.
The same care applies to a quality term without a stated method. “Good recovery” may be an informal observation rather than a calculation or acceptance finding. Keep the original observation identifiable and request the defined measurement where the project requires it.
Total recovery, an assessment of intact pieces, sample condition and suitability for a laboratory test answer different questions. If the project uses RQD or another defined index, use the approved method and reviewer. Do not rename a total recovery field as a different quality measure or treat either as a mineral grade result.
After an unresolved run: preserve the question
The following example is fictional. It illustrates record status and responsibility without calculating recovery or reconstructing missing rock.
The file for run EX-A includes a description of the recovered material, but the end-of-run reference conflicts with another record. A receiving technician notices the difference. The record can preserve the observation while marking the interval for review.
| Entry | What the record should communicate |
|---|---|
| Material observation | Preserved as recorded, with its recorder and method reference |
| Interval status | Unresolved because two identified records disagree |
| Evidence links | The original entries and any relevant supporting documents |
| Assigned review | The named project role responsible for resolving the discrepancy |
| Later decision | A dated explanation linked to the original record |
Do not make the record look complete by inserting the nominal barrel length. Do not move recovered material in the documentation as though the exact location of a loss had been demonstrated. The team’s accepted review process should resolve what can be resolved and retain uncertainty where evidence is insufficient.
This approach helps the next reader distinguish a difficult drilling result from an incomplete record. Those may require different responses, and concealing one inside the other makes later review harder.
Correct core sample quality records without losing the reason for the change
For core sample quality records, agree how a corrected entry will relate to the original, including the author, date, reason and supporting evidence. A spreadsheet value changed without context may remove the visible discrepancy while leaving no explanation of how the new value was established.
Corrections should flow to the places that rely on the record. Identify the responsible people and linked records rather than assuming every recipient uses a single current file. If a decision remains provisional, communicate that status with the data.
The goal is a readable history, not unnecessary paperwork. A short, clearly linked correction can be more useful than a long narrative that never identifies the affected run or the accepted change.
Agree the handover before the samples move
Define which records accompany the material, who checks their completeness and how the receiving team reports a discrepancy. The physical box identifiers and transport process need their own linked arrangements. Core sample quality records carry the quality observations and review history.
Link physical samples with written records and records of subsequent sampling. The relevant receiving facility’s own instructions govern its acceptance; local submission rules should not be treated as general requirements for other countries.
Analytical preparation choices depend on the project. Retain the actual laboratory’s requirements rather than assuming that a well-completed drilling record guarantees suitability for every test.
When discussing core drilling equipment with dragondrill, identify any configuration records the geology team needs from the equipment provider. Send those requirements through our quotation page or contact us to clarify the available documentation. Project quality methods, laboratory acceptance and geological interpretation need their own responsible specialists.
Questions about core sample quality records
Does total recovery describe every aspect of sample quality?
No. It does not replace observations about condition, other defined measurements or suitability for the intended analysis. Keep the project’s required fields and methods separate.
What should happen to an unresolved interval?
Keep the uncertainty and conflicting evidence visible, identify the affected record and assign review under the project’s process. Do not fill the gap with an assumed barrel length or an invented location for missing material.
Should a corrected entry erase the original?
Agree a traceable correction process that preserves the relationship, reason, author and date. The receiving team should be able to understand why the accepted record changed.