boulder opal
boulder opal · boulder opals
An opal consisting of concretions and fracture fillings in a dark siliceous ironstone…An opal consisting of concretions and fracture fillings in a dark siliceous ironstone matrix.
Meaning
1 senses(countable, uncountable)An opal consisting of concretions and fracture fillings in a dark siliceous ironstone matrix.
Forms
plural: boulder opals| Singular | boulder opal |
|---|---|
| Plural | boulder opals |
regular
Lessons for this word
1 lessons- A1Countable and uncountable nouns — Because it can be uncountable