How is beach sand different from other types of sand?

Answer 1

Beach sand is silica also but it has a lot of Calcium Carbonate in it from ground up oyster shell and other Calcium Carbonate sources; such as coral grit. It tends to be "sharp" new sand as opposed to the ground(and round) river sand.

Answer 2

Beach Sand is a mixture of fragments worn down from rocks and shells (throughout tropical Oceania, island sand comes from coral and other sea shells). Although the purest sands consist of quartz or coral material alone, most of the sand between your toes is a blend of about two-thirds quartz and other material (which can be up to 15% feldspar, 15% percent rock fragments, 5% clay minerals and smaller proportions of calcium carbonate, organic materials and other minerals).
When a grain of sand appears rough-edged under a microscope, not much time has passed since it has been weathered from bigger rocks and shells. The grains become rounder as physical abrasion and chemical weathering take their toll. Desert sand has the roundest grains of all, because the winds keep the particles shifting and hitting against one another constantly. On the dunes of the Sahara, for example, the wind drives not merely ripples, but vast waves of sand.
Sand grains are smaller than gravel but bigger than particles of silt (should you care to measure the difference, sand grains range in size from 0.0025 inches to 0.08 inches in diameter – or "a pinpoint to pencil lead", by naturalist Peter Meyer’s rule of thumb). Fine-grained sand forms a firm beach surface,

Answer 3

http://waynesword.palomar.edu/ww0704b.htm
http://www.microscope-microscope.org/applications/sand/microscopic-sand.htm
http://www.soest.hawaii.edu/GG/ASK/beach_sand.html