If you don't find what you need on our site, please contact us so we can assist you. Starbucks Online Store Customer Service Team. Customer Service Team hours are Monday through Friday, 5:30 a.m. - 5:00 p.m. PT, Saturday, 7:00am - 3:30pm PT, Sunday, closed. Call us toll-free at 1-877-421-9062. Contact the Starbucks Online Store Customer Service Team via e-mail using the form below:
The smallest particle visible to the naked eye is 40 microns. To give you some perspective, a piece of hair's width can range from 40 to 120 microns.
Nearly all diatoms are microscopic - cells range in size from about 2 microns to about 500 microns (0.5 mm), or about the width of a human hair (note that one micron is equal to 10-6 meter). Scientists use light microscopes (LM) or scanning electron microscopes (SEM) to view diatom structures.