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 Post subject: Don’t believe everything you read!
PostPosted: Tue May 16, 2017 10:22 am 
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Location: Bedfordshire
During my experimentation with crackle compositions, I have seen many reported formulations that, on testing, I have found not to work. Patent applications, especially those emanating from China, seem to be written with sufficiently vague specifications that the effects they claim are almost impossible to reproduce. I’ve learned not to believe any reported composition unless I know it to come from a reliable source.

Last week I spent a very pleasant morning chatting with a respected member of the professional community. Amongst other things, he told me a couple of stories about his experiences with Chinese manufacturers. In a list of the contents of imported fireworks, he noticed that copper oxide was listed more than once, each listing being accompanied by a different Chinese ideogram. He concluded that there must be something different about each of the copper oxides that appeared in the list.

On another occasion, during a visit to China, he saw an (unspecified) effect that he wanted to try, and was given the formulation, which contained copper oxide. On returning to the UK, he found he could not reproduce the effect that he had seen and got back in touch with his Chinese source. He was told he needed to use their particular type of copper oxide and they sent him a sample. He didn’t say whether it worked or not, but he did tell me that he found the ‘copper oxide’ to contain 17% potassium dichromate! He gave me a small sample and I've just run a quick and dirty solubility test on it, which confirmed the dichromate content to be about 15%.

The implication of all this seems to be that reported compositions are not only likely to be approximate in terms of the stated proportions, but may also contain unlisted ingredients. In the above example the unmentioned component is both toxic and carcinogenic, so I have to ask myself: how many other such cases exist?

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 Post subject: Re: Don’t believe everything you read!
PostPosted: Tue May 16, 2017 2:46 pm 
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Well like a said to you the other day CE marking stands for Chinese export no surprise that dichromate has been found in the copper oxide.

The most interesting thing is why, as dichromate is not cheap even to the Chinese.

Genuine CE marks are crippling the UK and Europe in the manufacturing of fireworks bring back the old British standards I say but I think it’s too late for the gentleman in question.


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 Post subject: Re: Don’t believe everything you read!
PostPosted: Tue May 16, 2017 4:58 pm 
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Yes - you're right Ken. I think it was Dr Wan's special copper Oxide mix.


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 Post subject: Re: Don’t believe everything you read!
PostPosted: Tue May 16, 2017 5:29 pm 
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Or maybe the Indian magic mix Sam


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 Post subject: Re: Don’t believe everything you read!
PostPosted: Fri May 19, 2017 7:02 pm 
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I don't understand why the country in question is exempt to all the normal import checks,watch fake Britain any week and we seem to import any rubbish and sub standard goods that can be imagined.Regards B


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