Nitrofurantoin (Macrodantin, Furadantin, Macrobid) is a drug available in three forms prescribed for the treatment or prevention of urinary tract infections (UTIs). Side effects, warnings and precautions, drug interactions, and patient information should be reviewed prior to taking any medication.
In this group the mineral is held together by the attraction between silica tetrahedra and other positive ions. Olivine and Garnet are examples of minerals within the independent tetrahedra group. Single chain silicates contain silica tetrahedra that are linked up in a chain by sharing two oxygen atoms. The most common single chain silicate is pyroxene. Double chain silicates form by sharing either two or three oxygen.
This behavior is called split growth. It is a very common phenomenon not only found in quartz. Some minerals frequently show split growth, like prehnite, epidote and, perhaps the best example, stilbite. Split growth may occur during an episode of crystal growth, for example, as a response to mechanical interference.