For tonnages and most grades, the smoothed curves represent percentiles of a lognormal distribution that has the same mean and standard deviation as the observed data; exceptions are plots where only a small percentage of deposits had reported grades and grade plots that are presented on an arithmetic scale, such as iron or manganese, for which the smoothed curve was fit by eye. These are important sources for:.what the word dice roulette 69 PKR $20 NO DEPOSIT BONUS MINERALS AND ORES SYLLABUS POINTS: o Define the terms mineral and ore with reference to economic and non-economic deposits of natural resources. o. I'm going to do a task of mineral and ore. Teacher required me to give a reference of econimic and non-economic deposit of natural resources, but I have no idea where can I find the reference. Please provide a website to me. Non-metallic Resources: • Sand, Gravel, Gypsum, Halite, Dimension stone. Economic deposits require concentration by geologic processes. Mineral Deposits.