Description: This specimen weighs 0.20 grams. It measures 18 mm x 4 mm x 3 mm. I offer a shipping discount for customers who combine their payments for multiple purchases into one payment! The discount is regular shipping price for the first item and just 50 cents for each additional item! To be sure you get your shipping discount just make sure all the items you want to purchase are in your cart. Auctions you win are added to your cart automatically. For any "buy it now" items or second chance offers, be sure to click the "add to cart" button, NOT the "buy it now" button. Once all of your items are in your cart just pay for them from your cart and the combined shipping discount should be applied automatically. I offer a money back guarantee on every item I sell. If you are not 100% happy with your purchase just send me a message to let me know and I will buy back the item for your full purchase price. Hi there. I am selling this amazing native silver crystal specimen. It is from Elura Mine (Endeavor Mine), Cobar, Robinson County, New South Wales, Australia. I hope it finds a good home out there, and I am sure it will. This piece is really beautiful. Thanks so much for visiting my auction and have a great day! The following is information about this mineral from wikipedia: SilverFrom Wikipedia, the free encyclopedia Silver, 47Ag SilverAppearancelustrous white metalStandard atomic weight Ar°(Ag)107.8682±0.0002[1]107.87±0.01 (abridged)[2]Atomic number (Z)47Groupgroup 11Periodperiod 5Block d-blockElectron configuration[Kr] 4d10 5s1Electrons per shell2, 8, 18, 18, 1Physical propertiesPhase at STPsolidMelting point1234.93 K (961.78 °C, 1763.2 °F)Boiling point2435 K (2162 °C, 3924 °F)Density (at 20° C)10.503 g/cm3[3]when liquid (at m.p.)9.320 g/cm3Heat of fusion11.28 kJ/molHeat of vaporisation254 kJ/molMolar heat capacity25.350 J/(mol·K)Vapour pressureP (Pa)1101001 k10 k100 kat T (K)128314131575178220552433Atomic propertiesOxidation states−2, −1, 0,[4] +1, +2, +3 (an amphoteric oxide)ElectronegativityPauling scale: 1.93Ionisation energies1st: 731.0 kJ/mol2nd: 2070 kJ/mol3rd: 3361 kJ/molAtomic radiusempirical: 144 pmCovalent radius145±5 pmVan der Waals radius172 pmColor lines in a spectral rangeSpectral lines of silverOther propertiesNatural occurrenceprimordialCrystal structureface-centred cubic (fcc) (cF4)Lattice constantFace-centered cubic crystal structure for silvera = 408.60 pm (at 20 °C)[3]Thermal expansion18.92×10−6/K (at 20 °C)[3]Thermal conductivity429 W/(m⋅K)Thermal diffusivity174 mm2/s (at 300 K)Electrical resistivity15.87 nΩ⋅m (at 20 °C)Magnetic orderingdiamagnetic[5]Molar magnetic susceptibility−19.5×10−6 cm3/mol (296 K)[6]Young's modulus83 GPaShear modulus30 GPaBulk modulus100 GPaSpeed of sound thin rod2680 m/s (at r.t.)Poisson ratio0.37Mohs hardness2.5Vickers hardness251 MPaBrinell hardness206–250 MPaCAS Number7440-22-4HistoryDiscoverybefore 5000 BCSymbol"Ag": from Latin argentumIsotopes of silverveMain isotopes[7]Decayabundancehalf-life (t1/2)modeproduct105Agsynth41.3 dε105Pdγ–106mAgsynth8.28 dε106Pdγ–107Ag51.8%stable108mAgsynth439 yε108PdIT108Agγ–109Ag48.2%stable110m2Agsynth249.86 dβ−110Cdγ–111Agsynth7.43 dβ−111Cdγ– Category: SilverSilver is a chemical element; it has symbol Ag (from Latin argentum 'silver', derived from Proto-Indo-European *h₂erǵ 'shiny, white') and atomic number 47. A soft, white, lustrous transition metal, it exhibits the highest electrical conductivity, thermal conductivity, and reflectivity of any metal.[8] Silver is found in the Earth's crust in the pure, free elemental form ("native silver"), as an alloy with gold and other metals, and in minerals such as argentite and chlorargyrite. Most silver is produced as a byproduct of copper, gold, lead, and zinc refining. Silver has long been valued as a precious metal. Silver metal is used in many bullion coins, sometimes alongside gold:[9] while it is more abundant than gold, it is much less abundant as a native metal.[10] Its purity is typically measured on a per-mille basis; a 94%-pure alloy is described as "0.940 fine". As one of the seven metals of antiquity, silver has had an enduring role in most human cultures. Other than in currency and as an investment medium (coins and bullion), silver is used in solar panels, water filtration, jewellery, ornaments, high-value tableware and utensils (hence the term "silverware"), in electrical contacts and conductors, in specialized mirrors, window coatings, in catalysis of chemical reactions, as a colorant in stained glass, and in specialized confectionery. Its compounds are used in photographic and X-ray film. Dilute solutions of silver nitrate and other silver compounds are used as disinfectants and microbiocides (oligodynamic effect), added to bandages, wound-dressings, catheters, and other medical instruments. Characteristics Silver is extremely ductile, and can be drawn into a wire one atom wide.[11]Silver is similar in its physical and chemical properties to its two vertical neighbours in group 11 of the periodic table: copper, and gold. Its 47 electrons are arranged in the configuration [Kr]4d105s1, similarly to copper ([Ar]3d104s1) and gold ([Xe]4f145d106s1); group 11 is one of the few groups in the d-block which has a completely consistent set of electron configurations.[12] This distinctive electron configuration, with a single electron in the highest occupied s subshell over a filled d subshell, accounts for many of the singular properties of metallic silver.[13] Silver is a relatively soft and extremely ductile and malleable transition metal, though it is slightly less malleable than gold. Silver crystallizes in a face-centered cubic lattice with bulk coordination number 12, where only the single 5s electron is delocalized, similarly to copper and gold.[14] Unlike metals with incomplete d-shells, metallic bonds in silver are lacking a covalent character and are relatively weak. This observation explains the low hardness and high ductility of single crystals of silver.[15] Silver has a brilliant, white, metallic luster that can take a high polish,[16] and which is so characteristic that the name of the metal itself has become a color name.[13] Protected silver has greater optical reflectivity than aluminium at all wavelengths longer than ~450 nm.[17] At wavelengths shorter than 450 nm, silver's reflectivity is inferior to that of aluminium and drops to zero near 310 nm.[18] Very high electrical and thermal conductivity are common to the elements in group 11, because their single s electron is free and does not interact with the filled d subshell, as such interactions (which occur in the preceding transition metals) lower electron mobility.[19] The thermal conductivity of silver is among the highest of all materials, although the thermal conductivity of carbon (in the diamond allotrope) and superfluid helium-4 are higher.[12] The electrical conductivity of silver is the highest of all metals, greater even than copper. Silver also has the lowest contact resistance of any metal.[12] Silver is rarely used for its electrical conductivity, due to its high cost, although an exception is in radio-frequency engineering, particularly at VHF and higher frequencies where silver plating improves electrical conductivity because those currents tend to flow on the surface of conductors rather than through the interior. During World War II in the US, 13540 tons of silver were used for the electromagnets in calutrons for enriching uranium, mainly because of the wartime shortage of copper.[20][21][22] Silver readily forms alloys with copper, gold, and zinc. Zinc-silver alloys with low zinc concentration may be considered as face-centred cubic solid solutions of zinc in silver, as the structure of the silver is largely unchanged while the electron concentration rises as more zinc is added. Increasing the electron concentration further leads to body-centred cubic (electron concentration 1.5), complex cubic (1.615), and hexagonal close-packed phases (1.75).[14] IsotopesMain article: Isotopes of silverNaturally occurring silver is composed of two stable isotopes, 107Ag and 109Ag, with 107Ag being slightly more abundant (51.839% natural abundance). This almost equal abundance is rare in the periodic table. The atomic weight is 107.8682(2) u;[23][24] this value is very important because of the importance of silver compounds, particularly halides, in gravimetric analysis.[23] Both isotopes of silver are produced in stars via the s-process (slow neutron capture), as well as in supernovas via the r-process (rapid neutron capture).[25] Twenty-eight radioisotopes have been characterized, the most stable being 105Ag with a half-life of 41.29 days, 111Ag with a half-life of 7.45 days, and 112Ag with a half-life of 3.13 hours. Silver has numerous nuclear isomers, the most stable being 108mAg (t1/2 = 418 years), 110mAg (t1/2 = 249.79 days) and 106mAg (t1/2 = 8.28 days). All of the remaining radioactive isotopes have half-lives of less than an hour, and the majority of these have half-lives of less than three minutes.[26] Isotopes of silver range in relative atomic mass from 92.950 u (93Ag) to 129.950 u (130Ag);[27] the primary decay mode before the most abundant stable isotope, 107Ag, is electron capture and the primary mode after is beta decay. The primary decay products before 107Ag are palladium (element 46) isotopes, and the primary products after are cadmium (element 48) isotopes.[26] The palladium isotope 107Pd decays by beta emission to 107Ag with a half-life of 6.5 million years. Iron meteorites are the only objects with a high-enough palladium-to-silver ratio to yield measurable variations in 107Ag abundance. Radiogenic 107Ag was first discovered in the Santa Clara meteorite in 1978.[28] 107Pd–107Ag correlations observed in bodies that have clearly been melted since the accretion of the Solar System must reflect the presence of unstable nuclides in the early Solar System.[29] ChemistryOxidation states and stereochemistries of silver[30]OxidationstateCoordinationnumberStereochemistryRepresentativecompound0 (d10s1)3PlanarAg(CO)31 (d10)2Linear[Ag(CN)2]−3Trigonal planarAgI(PEt2Ar)24Tetrahedral[Ag(diars)2]+6OctahedralAgF, AgCl, AgBr2 (d9)4Square planar[Ag(py)4]2+3 (d8)4Square planar[AgF4]−6Octahedral[AgF6]3−Silver is a rather unreactive metal. This is because its filled 4d shell is not very effective in shielding the electrostatic forces of attraction from the nucleus to the outermost 5s electron, and hence silver is near the bottom of the electrochemical series (E0(Ag+/Ag) = +0.799 V).[13] In group 11, silver has the lowest first ionization energy (showing the instability of the 5s orbital), but has higher second and third ionization energies than copper and gold (showing the stability of the 4d orbitals), so that the chemistry of silver is predominantly that of the +1 oxidation state, reflecting the increasingly limited range of oxidation states along the transition series as the d-orbitals fill and stabilize.[31] Unlike copper, for which the larger hydration energy of Cu2+ as compared to Cu+ is the reason why the former is the more stable in aqueous solution and solids despite lacking the stable filled d-subshell of the latter, with silver this effect is swamped by its larger second ionisation energy. Hence, Ag+ is the stable species in aqueous solution and solids, with Ag2+ being much less stable as it oxidizes water.[31] Most silver compounds have significant covalent character due to the small size and high first ionization energy (730.8 kJ/mol) of silver.[13] Furthermore, silver's Pauling electronegativity of 1.93 is higher than that of lead (1.87), and its electron affinity of 125.6 kJ/mol is much higher than that of hydrogen (72.8 kJ/mol) and not much less than that of oxygen (141.0 kJ/mol).[32] Due to its full d-subshell, silver in its main +1 oxidation state exhibits relatively few properties of the transition metals proper from groups 4 to 10, forming rather unstable organometallic compounds, forming linear complexes showing very low coordination numbers like 2, and forming an amphoteric oxide[33] as well as Zintl phases like the post-transition metals.[34] Unlike the preceding transition metals, the +1 oxidation state of silver is stable even in the absence of π-acceptor ligands.[31] Silver does not react with air, even at red heat, and thus was considered by alchemists as a noble metal, along with gold. Its reactivity is intermediate between that of copper (which forms copper(I) oxide when heated in air to red heat) and gold. Like copper, silver reacts with sulfur and its compounds; in their presence, silver tarnishes in air to form the black silver sulfide (copper forms the green sulfate instead, while gold does not react). While silver is not attacked by non-oxidizing acids, the metal dissolves readily in hot concentrated sulfuric acid, as well as dilute or concentrated nitric acid. In the presence of air, and especially in the presence of hydrogen peroxide, silver dissolves readily in aqueous solutions of cyanide.[30] The three main forms of deterioration in historical silver artifacts are tarnishing, formation of silver chloride due to long-term immersion in salt water, as well as reaction with nitrate ions or oxygen. Fresh silver chloride is pale yellow, becoming purplish on exposure to light; it projects slightly from the surface of the artifact or coin. The precipitation of copper in ancient silver can be used to date artifacts, as copper is nearly always a constituent of silver alloys.[35] Silver metal is attacked by strong oxidizers such as potassium permanganate (KMnO4) and potassium dichromate (K2Cr2O7), and in the presence of potassium bromide (KBr). These compounds are used in photography to bleach silver images, converting them to silver bromide that can either be fixed with thiosulfate or redeveloped to intensify the original image. Silver forms cyanide complexes (silver cyanide) that are soluble in water in the presence of an excess of cyanide ions. Silver cyanide solutions are used in electroplating of silver.[36] The common oxidation states of silver are (in order of commonness): +1 (the most stable state; for example, silver nitrate, AgNO3); +2 (highly oxidising; for example, silver(II) fluoride, AgF2); and even very rarely +3 (extreme oxidising; for example, potassium tetrafluoroargentate(III), KAgF4).[37] The +3 state requires very strong oxidising agents to attain, such as fluorine or peroxodisulfate, and some silver(III) compounds react with atmospheric moisture and attack glass.[38] Indeed, silver(III) fluoride is usually obtained by reacting silver or silver monofluoride with the strongest known oxidizing agent, krypton difluoride.[39]
Price: 64.99 USD
Location: Tucson, Arizona
End Time: 2024-11-16T03:04:07.000Z
Shipping Cost: 5.95 USD
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Item Specifics
Restocking Fee: No
Return shipping will be paid by: Seller
All returns accepted: Returns Accepted
Item must be returned within: 30 Days
Refund will be given as: Money Back
Size: 18 mm x 4 mm x 3 mm
Country/Region of Manufacture: Australia
Weight: 0.20 grams
