The experimental search for metallic hydrogen has been active for over two decades with the first claims being published in 1975, followed by several others all of which failed to pass the test of time. The present paper describes experiments in which several important changes were made in the experiment, compared to those performed previously, which enabled us to reach a pressure of 342 GPa. The path was strewn with 15 pairs of carefully chosen diamonds. At 342 GPa visible light was readily transmitted through the sample proving that it was not yet an alkali metal. The reasons why it has been so difficult to achieve the required pressure for metallization will be discussed.
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