(75.0% gold) 14 kt is 14 parts gold and 10 parts total of silver and copper. It is only about as hard as your fingernail. Gold occurs in hydrothermal veins deposited by ascending solutions, as disseminated particles through some sulfide deposits, and in placer deposits. Mohs invented a scale of hardness based on how one mineral scratched another. 0000022232 00000 n 0000026556 00000 n It is highly prized by people because of its attractive color, its rarity, resistance to tarnish, and its many special properties - some of which are unique to gold. (58.3%) 10 kt is 10 parts weight of gold to 14 parts of other metals. (41.6%) Because Gold is so much heavier than the other metals, the actual amount of gold, by volume, in the different alloys is much less. Although there are about twenty different gold minerals, all of them are quite rare. 0000001957 00000 n %PDF-1.6 %���� xref Gold is an electrical conductor used in computers, circuits, appliances, cell phones, etc. Hard gold commonly has a hardness between 130-200 HK 25 with a hardness of up to 200 HK 25 possible. endstream endobj 58 0 obj <> endobj 59 0 obj <> endobj 60 0 obj <>/Encoding<>>>>> endobj 61 0 obj <>/Font<>/ProcSet[/PDF/Text]/ExtGState<>>>/Type/Page>> endobj 62 0 obj <> endobj 63 0 obj <> endobj 64 0 obj [/ICCBased 83 0 R] endobj 65 0 obj <>stream The top ten gold-producing countries are shown in green on the map above. It is resistant to the effect of most acids and therefore does not corrode easily. 0000030437 00000 n 1997. The Mohs Scale of Hardness for Metals 0000013233 00000 n 0000027185 00000 n To use an example, one of the hardest substances on earth, diamond, is rated 10 on the Mohs scale, while plastic and pencil lead, for instance, are on the other end of the scale, with a hardness grade of 1. 0000001610 00000 n %%EOF Native gold is an element and a mineral. 0000022693 00000 n Dental work, gilding, and many other uses. Gold is one of the first minerals used by prehistoric cultures. ��D�E"��H(ňăG������RE�,�N�_TJ��DרOD��D��~Q_#Z.�}&�����l�O��黢oX�ҾW�~M��b�&z,}�����?x���3����ߠ~���ܿk������[�Z��ZI��sഁ;�����⟻9�o�ǃ�~8d���Cg� �;�z�A�_�y �y~��)��~!�{���=�!�(m�s��{#. So, generally speaking gold is not a highly reactive compound. Gold Nuggets from Colorado. 57 0 obj <> endobj startxref 0000004380 00000 n About 10% is used in coinage or in the financial stores of governments. Native gold is an element and a mineral.It is highly prized by people because of its attractive color, its rarity, resistance to tarnish, and its many special properties - some of which are unique to gold. THE HARDNESS OF SPUTTERED GOLD FILMS Gold films 20-25 ftm thick were deposited by the magnetically enhanced sputtering of a 99.99% pure gold target onto thick polished nickel coupons. This specimen is approximately 1 inch (2.4 centimeters) across. 0000013651 00000 n The normal force of a contact should be considered when specifying hard vs soft gold plating. 0000014326 00000 n You will not be able to measure gold electroplate hardness on the surface with a diamond indentor unless the gold is at least 20 microns thick, you will have to do it on a section, for which it will have to be at least 10 microns thick if you use a 1gm load. 0000021829 00000 n x�b```b``�``e`�� Ā B,@Q���R� =D�&�e5����pJU��bi��w���.\k����� ۋT������^��=��kJ��=Q+�%X�9�ӌ�AK7�+�������5Y�#\�{��T�&��mO��w�] ���Y\\< � j s�!�RRҀ���PP�B���``;�HK�XD����g�[CmE�b�۶�8q���~�6X�(�rz8v%ɜ`vz�u2�r�k�@��aLb�[email protected]�-`�����C������T�.\������҂��7j�[� J�e� Whitens when naturally alloyed with silver. 0000001297 00000 n 0000003184 00000 n Therefore the objective of a first series of experiments has been to increase the hardness in the as-cast state without impairment of … Therefore, most gold found in nature is in the form of the native metal. #ã���"�7�Qρe��/M,�#�^�$*:!ƹh�K�FN��WG.�������4e䢈���bG�� ���c�ԉ�"1- ���)�/-�s"?��A$�$�'}"���Ddn�HT$�DQ"�F$ 18 kt is 18 parts gold and 6 parts total of silver and copper. 10 being the best and the most durable… Diamond is a 10. <]>> 0000000876 00000 n 6� "[email protected]�u:0�@��iQD�FM��&ט�{SL]g�'���X��w�����=�>�l�^k�������gĢ�}Db�x���KV�\:im�|h�2��� ����(���