Refractive index
Definition and Calculation of Refractive Index The refractive index is a dimensionless number that indicates the light bending ability of an optical medium. It determines the amount of light that...
Glossary
Refraction
Definition and Explanation of Refraction Refraction is the redirection of a wave as it passes from one medium to another. It can be caused by a change in the wave's...
Reflection (physics)
Reflection of light Reflection of light can be either specular (mirror-like) or diffuse (retaining energy but losing the image). Specular reflection occurs at the surface of a mirror or transparent...
Prism (optics)
Types of Prisms Dispersive prisms break up light into its constituent spectral colors. Reflective prisms are used to reflect, invert, rotate, or deviate light. Depolarizer prisms can alter the polarization...
Premier Mine
Notable discoveries The Cullinan Diamond is the largest rough gem-quality diamond ever found, weighing 3,106.75 carats (621.350g). The Premier Rose is a rough diamond weighing 353 carats (70.6g). The Niarchos...
Pre-engagement ring
Appearance and Customization Designs of pre-engagement rings may vary, featuring hearts, entangled designs, and other designs. Bands can be made of materials like titanium, silver, gold, wood, glass, ceramic, bone,...
Precious metal
Bullion and Purity Precious metals in bulk form are known as bullion and are traded on commodity markets. Bullion can be cast into ingots or minted into coins. The value...
Precious coral
Habitat and Anatomy Red corals grow on rocky seabottom with low sedimentation. They are typically found in dark environments, either in the depths or in dark caverns or crevices. The...
Prasiolite
Prasiolite as a green variety of quartz Prasiolite is a green variety of quartz. It is also known as green quartz, green amethyst, or vermarine. Most natural prasiolite comes from...