Port Director
Service Port-Milwaukee
4915 S. Howell Avenue
Suite 200
Milwaukee, WI 53207

ATTN: Lisa Ashmus, Import Specialist

RE: Application for Further Review of Protest No. 3701-11-100019; Tariff classification of glass-ceramic slabs.

Dear Port Director:

This letter is in reply to the Application for Further Review (“AFR”) of Protest number 3701-11-100019, filed September 16, 2011, on behalf of Technical Products Inc. (“Tech Inc.”/”Protestant”). The Protest is against U.S. Customs and Border Protection’s (“CBP”) classification of glass-ceramic slabs as worked glass under heading 7006 of the Harmonized Tariff Schedule of the United States (“HTSUS”).


The articles at issue in this AFR are glass-ceramic slabs composed of flourophlogopite mica and borosilicate glass, of which the brand name is MACOR® (“Macor slabs”). They are from machinable opaque glass ceramic, have the dimensions of 33 cm x 30 cm x 5.4 cm, and they can be machined into complicated shapes and precision parts with ordinary metalworking tools. The importer buys the Macor slabs from the manufacturer and either resells them to customers who machine the articles themselves or the importer will machine the slabs for customers into whatever shapes they desire. Examples of products made from machining the slabs include insulators, medical components, hinge points, aerospace components, microwave oven parts, scientific instruments, and nozzle tips for oxyacetylene torches.

An examination of a sample slab reveals that it has smooth rounded edges on six of its eight edges, with a slightly concave indentation on one side, and the other five sides have a wrinkled like appearance/texture and the slab is generally smooth to the touch.

According to the information provided, the slabs go through a seven step manufacturing process. In step (1), different raw materials, which include Silicon Dioxide (SiO2), Magnesium Oxide (MgO), Aluminum Oxide (Al2O3), Potassium Oxide (K2O), Boron Trioxide (B2O3), and Fluorine (F) are mixed together in batches. In step (2), the batch in step (1) is heated at a very high temperature (above 2000 °F) to bring it to a molten vitreous state. In step (3), the molten glass is poured into molds and cast to the desired slab shapes. In step (4), the slabs are removed from the casting molds (the edges of the slabs are rounded at this point) and put into a kiln known as a Lehr where it goes through the annealing process. In step (5), the annealed slabs are fired (cerammed) in a static oven and opacified. Step (6) involves quality control testing and in step (7) the shapes that are salable shapes are packed in wooden crates for shipment to customers (such as the importer or the customers the importer sells to) who would machine them to create specific articles.

The AFR involves eight entries for articles entered between the dates May 12, 2010, and February 10, 2011, inclusively, classified by the importer under subheading 7003.12.00, HTSUS, as “[c]ast glass and rolled glass, in sheets or profiles, whether or not having an absorbent, reflecting or non-reflecting layer, but not otherwise worked: [n]onwired sheets: [c]olored throughout the mass (body tinted), opacified, flashed or having an absorbent, reflecting or non-reflecting layer.” CBP liquated all the entries on April 1, 2011, classified under subheading 7006.00.40, HTSUS, as “[g]lass of heading 7003, 7004 or 7005, bent, edge-worked, engraved, drilled, enameled or otherwise worked, but not framed or fitted with other materials: [o]ther: [o]ther: [o]ther.” Tech Inc. filed its Protest and AFR on September 16, 2011, asserting that the glass-ceramic slabs are classifiable under heading 7003, HTSUS, as unworked sheets of cast glass.


Whether the glass-ceramic slabs are classified as cast glass under heading 7003, HTSUS, or as worked glass under heading 7006, HTSUS?


Initially, CBP notes that the Protest was timely filed on September 16, 2011, which is within 180 days after the liquidation date of April 1, 2011. See 19 U.S.C. § 1514(c)(3). Additionally, CBP’s classification of the merchandise is a protestable matter under 19 U.S.C. § 1514(a)(2).

Further Review of Protest No. 3701-11-100019 is properly accorded to Protestant pursuant to 19 C.F.R. § 174.24(a). The Protestant asserts that CBP’s classification of the articles is inconsistent with CBP rulings, which concern the same or substantively similar merchandise, namely Headquarters Ruling Letter (“HQ”) HQ 952809, dated December 1, 1992.

Classification under the HTSUS is made in accordance with the General Rules of Interpretation (GRI). GRI 1 provides that the classification of goods shall be “determined according to the terms of the headings and any relative section or chapter notes.” In the event that the goods cannot be classified solely on the basis of GRI 1, and if the headings and legal notes do not otherwise require, the remaining GRI 2 through 6 may be applied in order.

The following HTSUS provisions are under consideration:

7003 Cast glass and rolled glass, in sheets or profiles, whether or not having an absorbent, reflecting or non-reflecting layer, but not otherwise worked:

7006 Glass of heading 7003, 7004 or 7005, bent, edge-worked, engraved, drilled, enameled or otherwise worked, but not framed or fitted with other materials:

The Legal Notes to Chapter 70, HTSUS, provide in pertinent part the following:


* * * 2. For the purposes of headings 7003, 7004 and 7005: Glass is not regarded as “worked” by reason of any process it has undergone before annealing; Cutting to shape does not affect the classification of glass in sheets; The expression “absorbent, reflecting or non-reflecting layer” means a microscopically thin coating of metal or of a chemical compound (for example, metal oxide) which absorbs, for example, infrared light; or which improves the reflecting qualities of the glass while still allowing it to retain a degree of transparency or translucency; or which prevents light from being reflected on the surface of the glass. 3. The products referred to in heading 7006 remain classified in that heading whether or not they have the character of articles.

* * * * *

In understanding the language of the HTSUS, the Explanatory Notes (ENs) of the Harmonized Commodity Description and Coding System, which constitute the official interpretation of the Harmonized System at the international level, may be utilized. The ENs, although not dispositive or legally binding, provide a commentary on the scope of each heading, and are generally indicative of the proper interpretation of the HTSUS. See T.D. 89-80, 54 Fed. Reg. 35127 (August 23, 1989).

The ENs to Chapter 70 provide in pertinent part: * * * * * This Chapter also covers: * * * Special materials known as glass ceramics, in which the glass is converted into an almost wholly crystalline material by a process of controlled crystallization. They are made by adding to the glass batch nucleating agents which are often metal oxides (such as titanium dioxide and zirconium oxide) or metals (such as copper powder). After the article has been shaped by ordinary glass-making techniques, it is maintained at a temperature such as to ensure crystallization of the glassy body around the nucleating crystals (devitrification). Glass-ceramics may be opaque or sometimes transparent. They have much better mechanical, electrical and heat-resistant properties than ordinary glass. * * * * * The ENs to 70.03 provide in pertinent part:

This heading covers all types of cast glass and rolled glass provided it is in sheets (whatever the thickness and whether or not cut to shape), or profiles, whether or not having an absorbent, reflecting or non-reflecting layer, but not otherwise worked.

* * * * * (B)  A category of non-transparent glass which is more or less opacified in the mass and sometimes completely opaque. It is often made to resemble marble, porcelain (china) or alabaster in appearance. This type of glass is made in white, black and other colours, plain or veined, and is used for facing walls, for the manufacture of tops for washstands, counters, desks, tables, operating tables, etc., of tablets for gravestones, of advertising boards, signs, etc. * * * * *

The ENs to 70.06 provide in pertinent part: The heading includes:  (A)  Bent or curved glass such as the special glass (e.g., for display windows) which is obtained by hot-bending or hot-curving (in a suitable furnace and over moulds) flat glass sheets, with the exception, however, of the bent or curved glass of heading 70.15.  (B)  Glass with worked edges (ground, polished, rounded, notched, chamfered, bevelled, profiled, etc.), thus acquiring the character of articles such as slabs for table-tops, for balances or other weighing machinery, for observation slits and the like, for signs of various kinds, fingerplates, glasses for photograph frames, etc., window panes, glass fronts for furniture, etc. * * * * *

(Emphases in original).

As a preliminary matter, the glass-ceramic articles at issue are classifiable under Chapter 70, HTSUS, as the ENs to Chapter 70, HTSUS, specifically state that special materials, described as glass-ceramics, are covered in Chapter 70. The glass-ceramic slabs are manufactured in the processes as described in the General ENs to Chapter 70 and the articles possess characteristics of opacity and different mechanical, electrical and heat-resistant properties than ordinary glass. The competing headings at issue here are headings 7003, and 7006, HTSUS.

The ceramic-glass slabs are manufactured by the casting process into slabs. Glass that is cast into sheets is classifiable under heading 7003, HTSUS, as long as such glass has not been worked. The tariff term “worked” is not explicitly defined in Chapter 70, HTSUS. “When a tariff term is not defined in either the HTSUS or its legislative history, the term’s correct meaning is presumed to be its common meaning in the absence of evidence to the contrary.” Timber Prods. Co. v. United States, 515 F.3d 1213, 1219 (Fed. Cir. 2008). In discerning this common meaning, dictionaries, encyclopedias, scientific authorities, and other reliable information sources may be consulted to construe the meaning of a statute’s words. See Len-Ron Mfg. Co. v. United States, 334 F.3d 1304, 1309 (Fed. Cir. 2003). The Court of International Trade determined that the common meaning of “work” under the HTSUS is “to form, fashion, or shape an existing product.” Winter-Wolff, Inc. v. United States, 22 C.I.T. 70, 78-79 (1998). See also HQ W968361, dated July 14, 2008. An existing product is one that “already exists as a commercial product.” Winter-Wolff, 22 C.I.T. at 79. Thus, as a threshold, for an article to be considered “worked”, the process a glass article is subjected to would have to be performed on an existing commercial product.

In addition, the term “worked” is limited by Note 2(a), Chapter 70, which directs that any process glass has undergone before annealing is not considered “worked.” See HQ 960274, dated October 9, 1997 (stating that polishing or rounding operations listed in the heading 7006 ENs must be limited to those which occur after the annealing stage). The ENs to heading 7006 provide some examples of processes that, if applied after annealing on an existing product, would be considered “worked” for classification purposes. These processes include, but are not limited to, glass that is bent, curved, worked edges (ground, polished, rounded, notched, chamfered, beveled, profiled, etc.), perforated, fluted, and surface-worked glass (sand-blasted, rendered dull by treatment with emery or acid, frosted, engraved, etc.). However, not every process that an article is subjected to and that occurs after annealing would automatically direct finding the article to be considered “worked.” The appearance of an article can be evidence of further working, but is not dispositive. The actual test for whether an article has been “worked” requires a factual inquiry into its manufacture and any subsequent processing prior to importation. See HQ W968361.

As described supra, the processes involved in manufacturing the Macor slabs are the fundamental steps in the manufacture of the basic glass-ceramic material. Besides the fact that any process that occurs during and prior to annealing does not qualify as “worked”, overall there is nothing in the list of these manufacturing processes that is similar to the listed examples of “worked” in EN 70.06. Processing glass in a kiln would not be considered “worked” because such a process would be required to make the fundamental glass-ceramic substance. See HQ 952809, dated Dec. 1, 1992 (classifying unpolished glass-ceramic sheets as unworked cast glass under heading 7003, HTSUS).

An examination of the sample glass-ceramic slab provided does not reveal any mechanical polishing, edge-work, or any other type of features that occurred after annealing which would be considered “worked.” The rounded edges of the Macor slabs are formed naturally during the casting process but prior to the annealing process as is indicated by the exhibits provided that show the glass-ceramic slabs to have the rounded edges (only six of the slab’s eight edges are rounded) when the slabs are removed from the molds and at the end of the annealing process. In addition, superheating glass in a kiln can also naturally result in rounded edges with a polished looked, which is sometimes referred to as “fire polishing.” This is simply the natural behavior of glass when heated to high temperatures. Furthermore, some shrinkage occurs during the cooling process of the molten glass in the mold. The dip or indentation present on one side of the slab is caused by the fact that the surface of the molten glass cools at a different rate (quicker) than the molten glass that is inside and at the bottom of the mold.

The opacification of the slabs, which occurs after annealing, is not considered “worked.” Opacification is explicitly provided for in subheading 7003.12.00, HTSUS, and is noted in EN 70.03(B) as being one of the features of glass that is covered under heading 7003.

The step of ceramming/firing is also not considered “worked” for classification purposes, primarily because this is the step where crystallization of the glass occurs and hence, makes the actual basic glass-ceramic material. Although this step comes after annealing, it is the final step to actually manufacture the basic glass-ceramic material. The Macor slabs are not subjected to any additional processes or operations after the ceramming step that forms the glass-ceramic materials.

Therefore, because the ceramic-glass slabs are not worked, they are classifiable under heading 7003, HTSUS, as “[c]ast glass and rolled glass, in sheets or profiles, whether or not having an absorbent, reflecting or non-reflecting layer, but not otherwise worked.”


Pursuant to GRI 1, the MACOR® glass-ceramic slabs are classified under subheading 7003.12.0000, HTSUSA, as “[c]ast glass and rolled glass, in sheets or profiles, whether or not having an absorbent, reflecting or non-reflecting layer, but not otherwise worked: [n]onwired sheets: [c]olored throughout the mass (body tinted), opacified, flashed or having an absorbent, reflecting or non-reflecting layer.” The column one, rate of duty, is 1.4 percent ad valorem.

The Protest should be GRANTED. Since the classification indicated above is a different provision as the classification under which the entry was liquidated, you are instructed to grant the protest in full and reliquidate the entry pursuant to subheading 7003.12.00, HTSUS. A copy of this ruling should be attached to the CBP Form 19 and provided to the protestant as part of the notice of action on the protest.

Sixty days from the date of the decision the Office of International Trade, Regulations and Rulings, will make the decision available to CBP personnel, and to the public on the U.S. Customs and Border Protection Home Page on the World Wide Web at, by means of the Freedom of Information Act, and other methods of public distribution.


Myles B. Harmon, Director
Commercial and Trade Facilitation Division