Let me try to answer the later part of your query. You have raised the question about the possible names of the next two levels after the platinum level and the point has been missed by almost all authors above.
It appears that the levels - bronze, silver, gold, diamond and platinum has something to do with the nomenclature adopted in naming the anniversaries mostly the wedding anniversaries. Also, the value of the precious substances has also been used in naming the hierarchy of years.
The system prevalent in describing the wedding anniversaries in terms of completed years is - silver (25) – ruby (40) – gold (50) – diamond (60) – and platinum (70). Since the human couples generally have a married life longer than 70 years only in rare cases, nobody bothered to name the wedding anniversary on completion of 80, 90 or 100 years of married life.
I would suggest the names of next two levels as 'Rhodium Level' after completion of 3,00,000 points and 'Radium Level' after completion of 5,00,000 points.
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