leaching. Phosphate leached from guano phosphatizes the underlying rocks in some areas, forming apatite where the host rock is limestone and forming aluminum- or aluminum-iron-phosphate minerals where the underlying rock is a silicate. Individual deposits of both igneous apatite and marine phosÂ­
Medicare Part B (Medical Insurance) covers diagnostic hearing and balance exams if your doctor or other health care provider orders these tests to see if you need medical treatment. Medicare doesn't cover routine hearing exams, hearing aids, or exams for fitting hearing aids.
Learn about what items and services Medicare Part A and Part B doesn't cover. You'll have to pay for the items and services yourself unless you have other insurance or you're in a Medicare health plan that covers them.ead about what Medicare Part A (hospital insurance) covers, including inpatient care at a hospital, skilled nursing facility (SNF), and hospice.