Meticulously Designed

grammar help: ‘–design popular in the 19th century or — a design popular in the 19th century’? with or w/o a

The whole sentence is: “the mask is meticulously decorated by delicate patterns carved in high relief — design popular in the 19th century.’ Should I change the last sentence to ‘a design popular in the 19th century’ instead? Is the ‘a’ necessary?

I would change ‘by’ to ‘with’. By would refer to the carver or artist. You then have to decide what you are refering to – the delicate patterns or the high relief carving. If the former, you need to give some description of the patterns to use the ‘a design—’ option. If the latter, the ‘high relief’, I would change ‘design’ to ‘technique’. It would then read, ‘the mask is meticulously decorated with delicate patterns carved in high relief — a technique popular in the 19th century’.
When a passage is taken out of context, it is not always possible to understand the intentions of the writer. I hope this may be of some help.

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