These modified cuts tend to have a crushed ice or needle like facet pattern, more similar to a radiant cut than a traditional cushion cut. The chart below serves as a general guideline for evaluating the cut of a cushion cut diamond.
Broadly speaking, two types of stem cell can be distinguished: embryonic stem (ES) cells which can only be derived from preâimplantation embryos and have a proven ability to form cells of all tissues of the adult organism (termed âpluripotentâ), and âadultâ stem cells, which are found in a variety of tissues in the fetus and after birth and are, under normal conditions, more specialized (âmultipotentâ) with an important function in tissue replacement and repair.
Though some experiments have shown that adult stem cells can be useful, the most promising results come from embryonic stem cells derived from a 5-7 day embryo and embryonic germ cells, derived from aborted fetuses. Each of the sources of stem cells poses its own ethical questions.dult tissues also contian stem cells, ulike that of the embryonic stem cells and embryonic germ cells these are generally multipotent and only develop into cells of a specific tissue or organ type. These cells are in many types of adult tissues to replenish cells that wear out.