The material that possesses the highest electrical conductivity is silver.
Silver has the highest electrical conductivity among metals.
Silver exhibits the highest electrical conductivity among metals.
Silver has the highest conductivity among all known elements.
Silver has the highest electrical conductivity of all metals. It is highly conductive due to its free-moving electrons that allow electricity to flow easily through it.
Yes, indeed: one of the highest electrical conductivities of any known substance.
The highest degree of electrical conductivity is in silver.
Silver has the highest electrical conductivity among metals.
Silver exhibits the highest electrical conductivity among metals.
Silver is the best electrical conductor on the list. It has the highest electrical conductivity among all metals, making it a popular choice for electrical wiring and other applications where high conductivity is required.
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It would help if you specify whether you are talking about thermal conductivity, or electrical conductivity. Diamond certainly doesn't has the highest electrical conductivity. Its thermal conductivity is one of the highest known, and - if a synthetic diamond is made from pure (99.9%) C-12, it is indeed the highest. The Wikipedia article attributes this to a strong covalent bonding.
Silver has the highest conductivity among all known elements.
Silver
The best electrical-conducting materials are various superconductors, which display zero resistivity, or in other words perfect conductivity. Since about 1993, the highest-temperature superconductor known has been a ceramic material consisting of thallium, mercury, copper, barium, calcium and oxygen (HgBa2Ca2Cu3O8+δ) which is superconducting below 138 K. Several allotropes of carbon seem to share the palm for the highest electrical conductivity at room temperature. Graphene is one. Carbon nanotubes in the direction along the tube another. The known material with the highest thermal conductivity is a supercooled form of liquid helium: helium II The known material with the highest thermal conductivity at room temperature is graphene.
Silver has the highest electrical conductivity of all metals. It is highly conductive due to its free-moving electrons that allow electricity to flow easily through it.
The carbon allotrope we call diamond has the highest thermal (heat) conductivity of any material. It is far better an any metal (or anything else we know of) at allowing heat to pass through it. It is carbon (in its graphite allotrope) that has the highest electrical conductivity under normal conditions of any of the nonmetals. Any metal is a better electrical conductor, but carbon is good enough to make brushes for electrical motors out of. You'll recall that the brushes complete the electrical circuit between the wiring of the non-moving elements to the rotating commutator.
Someone wrote "what material has the highest R-value". This answer is not conducive to progress in their learning. The "r" in R-value stands for Resistance, that is, resistance to flow of heat. Conductivity is the reciprocal, or inverse, of the Resistivity. "Thermal Conductivity" is transfer of Heat. Since Heat is ultimately the jiggling around of small bits of Matter (fundamental particles like electrons, protons and neutrons), then atoms (assemblages of these 3 fundamental particles), then molecules (assemblages of similar or dissimilar atoms), or also the jiggling around of atoms within molecules) - then the material with the highest Resistivity would be the Absence of Matter, this is, Vacuum (not quite a material, strictly speaking, but "found" between the walls of a vacuum, or "Dewar", flask). For the material with (possibly) the lowest Resistivity, or highest Conductivity, try the Wikipedia article on "Thermal Conductivity". If you're a girl, it may be your best friend.