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These rips were almost certainly not caused by a machine given the very precise nature of the tear. One of them was just like you would make with a paper knife to open the envelope and just the size to let out a coin, the other I would find hard to believe was made by sorting machine as well. Also, as I pointed out, the coins were not loose in the envelope and did not feel to have hard edges due to the paper, tape and envelope they were encased in.
However, having said all that, I do wish people wouldn't send cash because of the dangers of it going 'missing' by whatever means.
I shall keep advocating my idea of Tesco gift cards as a method of payment.
Incidentally, did anyone see the item in the Daily Mail about a poison spider in a bunch of Tesco grapes. That's my local store !!!