Elements and Performance Criteria

The range statement relates to the unit of competency as a whole. It allows for different work environments and situations that may affect performance. Bold italicised wording, if used in the performance criteria, is detailed below. Essential operating conditions that may be present with training and assessment (depending on the work situation, needs of the candidate, accessibility of the item, and local industry and regional contexts) may also be included.

Types of rough opal may include:
composite natural opal - doublets, triplets, mosaic and chip opals
natural opal type 1 - opal in one piece in its natural state apart from cutting and polishing
natural opal type 2 - opal naturally attached to the host rock - boulder opal
natural opal type 3 - opal intimately diffused as infilling in pores or between the grains of the host rock; matrix opal
varieties of opal:(N1 to N9 represents gradation form black to white in approximately 10% intervals)
black - opal which shows a play of colour within or on a black or very dark body tone (N1, N2, N3, N4)
dark - opal which shows a play of colour within or on a dark body tone (N5, N6)
light - opal which shows a play of colour within or on a light body tone (N7, N8, N9).
Appropriate storage conditions and locations may include:
depending on the value: in safe or in designated locked cupboard
display boxes and pockets
display cases
individually bagged
humidified atmosphere
safes and deposit boxes.
Ways in which damage might occur may include:
dehydration
exposure to halogen lights
extremes of temperature
general wear and tear
immersion in water
rough handling
surface damage and scratching.
Preventative measures may include:
humidifying atmosphere
keeping in bags.
Areas of risk may include:
lack of documentation
misplacement
theft.
Strategies for minimising risk and safeguarding opal may include:
alarm systems
banks (deposit boxes)
display cases
insurance
lighting
photographing
safes
scanning
security locks
systematic approach to storage and handling
thorough recording and documenting
use of standard procedures for handling, storage and documentation.
Stock control system may be:
manual or electronic
very simple in the case of small businesses.
Stock may be:
cutting and polishing consumables
equipment for production cutting
rough or cut opal.

The evidence guide provides advice on assessment and must be read in conjunction with the performance criteria, required skills and knowledge, range statement and the Assessment Guidelines for the Training Package.

Overview of assessment

Critical aspects for assessment and evidence required to demonstrate competency in this unit
Evidence of the ability to:
identify, explain and apply safe and appropriate procedures for the handling and storage of rough or cut and polished opal
evaluate the areas where there is risk of loss and theft and follow risk minimising procedures.
Context of and specific resources for assessment
Assessment must ensure access to:
various samples of rough and cut opal
bags
recording materials
scales
storage locations.
Method of assessment
A range of assessment methods should be used to assess practical skills and knowledge. The following examples are appropriate for this unit:
observation of processes and procedures
oral and/or written questioning of underpinning knowledge and skills
evaluation of the final product
review of portfolios of evidence
review of third-party workplace reports of on-the-job performance by candidate.
Assessment methods should closely reflect workplace demands (e.g. literacy) and the needs of particular groups (e.g. people with disabilities, and people who may have literacy or numeracy difficulties, such as speakers of languages other than English, remote communities and those with interrupted schooling).
Guidance information for assessment
Holistic assessment with other units relevant to the industry sector workplace and job role is recommended.