Board Thread:General Discussion/@comment-23986430-20131002051959/@comment-637683-20131003215730

Looks like all of your calculated chances are correct. If your luck is really poor and fall through all those cases, you get to the Coin drop:
 * 1/5000 for Amber Mosquito
 * 1/50 for Amber
 * 1/25 for Gems (equal chance of Amethyst, Topaz, Sapphire, Emerald, Ruby, Diamond)
 * 1/3 for Ores (equal chance of Copper, Iron, Silver, Gold, Tin, Lead, Tungsten, Platinum)
 * 1/5000 for Platinum Coins
 * 1/400 for Gold Coins
 * 1/30 for Silver Coins
 * otherwise Copper Coins