WCO Explanatory Notes reproduced for reference. © World Customs Organization. Verify against official WCO publication.
Subheading Explanatory Notes. Subheading 7104.10 Piezo-electric quartz has the rope*, when subjected to rnechanicai ressure, of producing an electric char e, the strength of whic varies in relation to the pressye a n t conversely, of converting into the differences in electric potential to which it is subjected. rnecLcal \ By reason of this pro erty, piezo-electric quartz is used in the electrical e uipment industry for various purposes : the manufacture of micmphones, loudspeakers, instnr~~~ents w transmitting or receiving ultrasonic waves, instruments for fixed frequency oscillations, etc. 'E The piezo-electric quartz falling in this subheading is generally in the form of thin sheets, plates, rods, etc., obtained by sawing synthebc quartz with a precision-cut along the line of electrical axis. Subheading 7104.20 The Explanatory Note to subheading 7103.10 applies, mutatis murandis, to this subheading. Subheading 7104.90 The Explanatory Note to subheadings 7103.91 and 7103.99 applies, mutatis mutandis, to this subheading. 71.05 - Dust and powder of natural or synthetic precious or semi-precious stones. 7105.10 - Ofdiamonds 7105.90 - Other This heading covers dust and powder obtained, for example, from the polishing or grinding of the stones covered by the three preceding headings. The most important of these powders are derived from diamonds and garnets. Natural diampnd dust and powder are obtained mainly by crushing " bort " (industrial grade diamond grams). Synthetic diamond dust and powder are produced by direct conversion, generally of graphite, at high temperatures and pressures. These dusts and powders differ from the diamonds of headin 71.02 and 71.04 in that, for practical purposes, they are too small to be mounted individua 1 . They are normally used for abrasive purposes. Their particle size generally does not exceeB1,000 micrometers (microns) but sizing is effected by sievin rather than by measuring individual particles. There can be a considerable degree of overlap etween the size of dust and powder particles and that of stones, but whereas stones are counted individually to determine quantity, dust and powder are weighed. Y Diamond dust and powder are used for the manufacture of grinding, polishing or honing wheels, cutters, polishing pastes, etc. Garnet powder is used mainly for the grinding of optical lenses or as an abrasive on a base of paper or other material. The heading does not cover artificial corundum powder (heading 28.18). Sub-chapter 11 PRECIOUS METALS AND METALS CLAD WITH PRECIOUS METAL 71.06 - Silver (including silver plated with gold or platinum), unwrought or in semimanufactured forms, or in powder form. 7 106.10 - Powder - Other : - - Unwrought 7106.92 - - Semi-manufactured 7106.91 This heading covers the various unwrought, semi-manufactured or powder forms of silver or of silver alloys (as defined in the General Explanatory Note), of gold-plated silver (silver gilt) or of silver plated with platinum. The heading does not, however, cover silver clad with precious metal. Silver is a white metal, not corroded by the atmosphere but tending to tarnish; it is the best conductor of heat and electricity, and is the most malleable and ductile metal after gold. It is very soft in its pure state, and consequently is frequently a110 ed with other metals. Unalloyed silver is, however, widely used in electrical applications rontacts, fuses, etc.), in cemm apparatus used in the chemical or food industries or in surgery, and as a plating metal. Under the provisions of Note 5 to this Chapter (see General Explanatory Note above), the silver alloys which may fall in this heading include : (1) Silver-copper alloys. The most important of these are used in the manufacture of coins or of goldsmiths' or s~lversmiths'wares; some are also used in the manufacture of electrical contacts. (2) Silver-copper-cadmium, silver-copper-titanium and silver-indium alloys, used in the manufacture of goldsmiths' or silversmiths' wares. (3) Silver-copper-zinc alloys, sometimes also containing cadmium, tin or phosphorus, used as solders. (4) Silver-antimony-tin-lead, silver-copper-lead, silver-cadmium and silver-thallium antifriction alloys. (5) Sintered silver-tungsten, silver-molybdenum, silver-nickel and silver-iron alloys, used to make electrical contacts. The heading covers silver and its alloys in the following forms : (I) Powder, usually in the form of finely divided powder, obtained by various mechanical or chemical processes. It is used in metallurgy and in the manufacture of metallising preparations for electronic applications and of conducting cements. The heading excludes powders or flakes prepared as colours, paints or the like e.g., made up with I other colourin matter or put u as a l i p d or asty dispersion in a binder or so vent); these fall in heading 32.0g 32.07 (11 uid ustres and simi ar compounds for the ceramic or glass industries), 31.08 to 32.10,32.12 or 31.13. P P (II) Unwrought silver in lumps, grains, in ots, cast bars, pellets, etc.; also native silver in lumps, nuggets, crystals, etc., separated om their gangues. B (111) Bars, rods, sections, wire, plates, sheets and strip. These are usually obtained by rolling or drawing; strip and discs, etc., may also be obtained by cuttin sheet silver. The heading includes silver thread for use in the textile indus provide!t it has not been spun or otherwise combined with textile yarn (Section fine sterile silver wire used for surgical sutures is, however, classified in heading 0.06. ?%cry The heading also covers metallo- a hitic blocks, plates, bars, rods, etc., with a basis of " carbon ",containing silver (see xp anatory Note to heading 38.01). dP (IV)Tubes and pi es (includin coiled tubing) provided that they are note made up into R specific identi able articles &., parts of chemcal apparatus). (V) Foil (for silvering) is usually obtained by hammering or beating thin sheets of silver separated by sheets of old-beaters' skin. This foil is generally put up in booklets and may be fixed to a backing o paper, plastics, etc. f However the headin excludes st ing foils (also known as blocking foils) composed of silver powder agg10rnerate8with gelatin3e or other binder, or of silver deposited on paper, plastics or other support (heading 32.12). (VI) Purls, span es and cuttings. Purls are small twists of silver wire used in embroidery or f trimmings. pangles and cuttings, used for the same purposes, are small pieces cut to geometric form (round, star-shaped, etc.) and usually pierced in the middle. The heading does not cover castings, sinterings, stampings, pressings, etc., in the form of blanks for articles of jewellery, etc., falling in sub-chapter IIJ.(e.g., settings, ring blanks, badges, flowers and figures). 71.07 - Base metals clad with silver, not further worked than semi-manufactured. Metal clad with precious metal (including base metal inlaid with precious metal) is defined in Note 7 to this Chapter and the General Explanatory Note to this Chapter. The alloys of tin, nickel, zinc and articularly of copper are sometimes clad with silver. Unalloyed copper and steel may also e clad in this way. Such metals are used in silversmiths' wares (tableware, articles of interior decoration, etc.), and in tubing, vessels and apparatus for the chemical or food industries. f Base metal clad with silver falling in this heading is usually in the form of bars, rods, sections, wire, plates, sheets, strip, tubes or pipes. In general, the revisions of Explanatory Note to heading 71.06 also apply, mutatis mutandis, to base metal cla with silver. 71.08 - Gold (including old plated with platinum) unwrought or in semi-manufactured forms, or in pow er form (+). d - - Powder 7108.12 - - Other unwrought forms 7 108.13 - - Other semi-manufactured forms 7 108.20 - Monetary 7108.11 This headin covers the various alloys (as efmed in the heading does not, 'f semi-manufactured or owder forms of gold or gold Note), or of 01 plated with platinum. The preclous metaf. B Gold has a characteristic yellow colour; it is not oxidised even at high temperature, and has remarkable chemical resistance to most reagents, including acids (aqua reeia, however, attacks it). It is, after silver and co per, the best conductor of heat and electrtci . It is the most malleable and most ductile o all metals, but is very soft, and is therefore rare y used unalloyed except for electro-plating, or as an electrodeposit. '7 P Under the terms of Note 5 to this Chapter (see General Explanatory Note), the gold alloys which may fall in this heading, include : (1) Gold-silver allo s, varying in colour from yellow throu* green to white, according to the proportions of t e constituent metals. They are used in jewellery and also in electrical contacts and in special high melting point solders. (2) Gold-co per alloys, used in the manufacture of coins, jewellery or goldsmiths' wares or in electrica contacts. P (3) Gold-silver-co er all0 s, primarily used in jewellery, oldsrniths' wares, in dental alloys or as solders. ese a1 o s ma contain zinc and ca ium and are then also used as solders. The alloy called "dore "or " bullion dark " consisting main1 of silver and co per falls in this heading when it contains 2 % or more, b we1 t, of go d. It is obtained om certain cupriferous pyrites or from residues derived om t e processing of blister copper and is subsequently refined to separate its constituent metals. # ? & g '$P r ! (4) Gold-co per-nickel alloys, sometimes containing added zinc and magnesium, ivin a range o alloys (known as " white " golds or, in some countries, as " grey" go1 s) ofen used as a substitute for latinurn. Other " white golds contain 2 % or more of palladium and are therefore eaclu ed (heading 71.10). P l % " (5) Gold-nickel alloys,used in the manufacture of electrical contacts. The heading includes gold and gold alloys in the same forms as those described for silver. The provisions of Explanatory Note to heading 71-06therefore apply, mutatis mutandis.
1.- Subject to Note 1 (A) to Section VI and except as provided below, all articles consisting wholly or partly : (a) Of natural or cultured pearls or of precious or semi-precious stones (natural, synthetic or reconstructed), or (b) Of precious metal or of metal clad with precious metal, are to be classified in this Chapter. 2.- (A) Headings 71.13, 71.14 and 71.15 do not cover articles in which precious metal or metal clad with precious metal is present as minor constituents only, such as minor fittings or minor ornamentation (for example, monograms, ferrules and rims), and paragraph (b) of the foregoing Note does not apply to such articles (). (B) Heading 71.16 does not cover articles containing precious metal or metal clad with precious metal (other than as minor constituents). 3.- This Chapter does not cover : (a) Amalgams of precious metal, or colloidal precious metal (heading 28.43); (b) Sterile surgical suture materials, dental fillings or other goods of Chapter 30; (c) Goods of Chapter 32 (for example, lustres); (d) Supported catalysts (heading 38.15); (e) Articles of heading 42.02 or 42.03 referred to in Note 3 (B) to Chapter 42; (f) Articles of heading 43.03 or 43.04; (g) Goods of Section XI (textiles and textile articles); (h) Footwear, headgear or other articles of Chapter 64 or 65; (ij) Umbrellas, walking-sticks or other articles of Chapter 66; (k) Abrasive goods of heading 68.04 or 68.05 or Chapter 82, containing dust or powder of precious or semi-precious stones (natural or synthetic); articles of Chapter 82 with a working part of precious or semi-precious stones (natural, synthetic or reconstructed); machinery, mechanical appliances or electrical goods, or parts thereof, of Section XVI. However, articles and parts thereof, wholly of precious or semi-precious stones (natural, synthetic or reconstructed) remain classified in this Chapter, except unmounted worked sapphires and diamonds for styli (heading 85.22); (l) Articles of Chapter 90, 91 or 92 (scientific instruments, clocks and watches, musical instruments); (m) Arms or parts thereof (Chapter 93); (n) Articles covered by Note 2 to Chapter 95; (o) Articles classified in Chapter 96 by virtue of Note 4 to that Chapter; or () The underlined portion of this Note constitutes an optional text.