If a gas fire gives off a green flame, is that a bad thing?

I've had a gas fire for quite a while now, but it was experiencing some problems about 6 months ago with it failing to turn on. That was fixed about a week later, but since then it was giving off green flames. Yesterday a friend told me this was a bad thing but she didn't know why, just a rumor she had... show more I've had a gas fire for quite a while now, but it was experiencing some problems about 6 months ago with it failing to turn on. That was fixed about a week later, but since then it was giving off green flames. Yesterday a friend told me this was a bad thing but she didn't know why, just a rumor she had heard. Is it true?
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