How to remove quotation marks from an array of strings

Given the following array of strings:
a = ["Chile", "Colombia"]
How is it possible to get a string like "Chile, Colombia", with or without quotation marks?

julia> a = ["Chile", "Colombia"]
2-element Vector{String}:

julia> join(a, ", ")
"Chile, Colombia"

Without quotation marks:

julia> print(join(a, ", "))
Chile, Colombia
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