End the use of fiscally unsustainable currency

It's no secret that it costs more than a penny to make a penny and for most people they don't value the penny anymore. You can't buy anything with only one penny and most end up saving them instead of spending them causing the mint to make more than what is actually needed. I would like to go with a suggestion I had heard where we end the penny, nickel, quarter and bring back the half dollar. We adjust prices to multiples of ten either by rounding up or down (instead of 99 cents it would round up to $1, or instead of 91 cents it would turn to 90 cents). I would also like to invest in alternative technologies to phase out the paper dollar. I would like to switch to a longer lasting plastic type of dollar. I believe Australia or Canada is working on this. reform=savings