Continental Trade Sp. z o. o.

Technical glass

Milky / Opaque / Satin quartz tubes

The opaque quartz tubes comes from quartz sands of high purity when reduced to a molten state at a temperature of approximately 2000° C. The high temperature produces a vitreous material characterized by the presence of a multitude of gaseous micro-bubbles. These bubbles diffract light, giving the material its opacity. The term opaque silica is mainly used for molded or centrifuged parts, while the product obtained by drawing is normally referred to as translucent.

Opaque quartz glass, due to the scattering of light in the micropores, is a very good thermal insulator, blocks infrared (IR) radiation, has a microporous structure with a high density and smooth surface. It is opaque, it can be used at high temperatures (constant operating temperature up to 1100 ° C) and chemically aggressive environments.

Available dimensions:

  • diameters: 6 mm - 80 mm
  • wall thickness: 0.5 mm - 5 mm

Choose the right inner diameter (ID), the outer diameter (OD) available for it, the required length (L) and the number of pieces, and then place your order by email or via the contact form.

Properties and chemical composition of opaque quartz as well as other types of quartz glass, are discussed in detail in chapter Our offer/Technical glass/Types of materials/Quartz glass.  

Properties of different types of glasses are discussed here. Bellow are shown properties of Milky Quartz Glass (called also: Opaque Quartz Glass or Satin Quartz Glass):


Milky (Opaque, Satin) Quartz Glass JGSM
Milky (Opaque, Satin) Quartz Glass Transmittance

Milky (Opaque, Satin) Quartz Glass JGSM

The opacity of a quartz glass is obtained by adding the air during the melting process of silica sand. At a temperature of approx. 2000 ° C produced a glassy material with lots of bubbles, causing light scattering and opacity suitable material.

The quality of the material is determined by the uniformity of distribution of bubbles, their size and shape. Many small vesicles (approx. 10 µm) scatter light better than bubbles large and very few (eg. 50 - 150 microns) - giving an opacity effect worse, especially at small thicknesses of material.

Milky quartz, known also as Opaque Quartz Glass or Satin Quartz Glass, due to scattering of radiation in the micropores, is a very good thermal insulator, blocks IR, has a microporous structure with a high density and smooth surface. It can be machined at a reasonable cost. It is opaque, it can be used at high temperatures (constant operating temperature up to 1100 ° C) and chemically aggressive environments.

Low porosity of the material allows to obtain properties similar to fused quartz, while the possibility of gas welding without material shrinkage smooth and without joints. It can be combined with a transparent quartz.

If applied flame polishing, the surface micropores disappears  (cicatrize), creating a clean, smooth surface. Does not arise the "orange peel" effect. In addition to improving cosmetic appearance, smoother surface allows the use of thin seals in vacuum applications. In addition, reduced porosity increases the resistance of the material of hydrofluoric acid (HF). Flame smoothed surfaces are smooth, even after long-term HF acid.

The advantages of material:

  • excellent thermal insulator
  • blocking UV and IR
  • high maximum operating temperature
  • very smooth surface
  • high chemical purity
  • high chemical resistance
  • good mechanical resistance
  • does not shrink during fire polishing,
  • can be easily welded to the transparent quartz,
  • easy sealing in high pressure applications.

Resistance to 5% hydrofluoric acid (HF)
Resistance to 5% hydrofluoric acid (HF)

Specialized applications requiring increased chemical and thermal resistance, high and uniform level of light scattering should be based on the use of materials produced by recognized manufacturers such as Heraus (OM100, RotoSil   OFM 70, OFM 370, 970 OFM OSC) or Momentive (GE514, GE544). 


Typical dimensions and tolerances

Tube dimensions


1,00 2,00   8,00 10,00   18,00 20,00   35,00 38,00
3,00   11,00   20,50   40,00
4,00   12,00   21,00   36,00 40,00
5,00   9,00 11,00   21,60   37,00 40,00
6,00   11,80   19,00 22,00   38,10 42,10
2,00 3,00   13,00   25,00   40,00 43,00
4,00   15,00   20,00 22,00   44,00
5,00   10,00 12,00   22,50   45,00
6,00   13,00   23,00   46,00
8,00   14,00   24,00   42,00 45,00
2,30 6,30   10,50 12,75   24,50   46,00
3,00 4,00   13,00   25,00   44,00 48,00
5,00   15,80   22,00 24,00   45,00 48,00
6,00   11,00 13,00   24,50   46,00 50,00
8,00   15,00   25,00   47,00 50,00
3,60 8,00   12,00 14,00   25,80   48,00 52,00
4,00 6,00   15,00   24,00 26,00   50,00 54,00
6,35   16,00   28,00   55,00
8,00   13,00 15,00   30,00   52,00 58,00
4,10 10,00   15,80   25,00 27,00   53,00 57,00
4,50 9,10   16,00   28,00   55,00 59,00
5,00 7,00   16,20   28,80   57,00 61,00
7,25   13,50 19,00   26,00 29,00   60,00 64,00
8,00   14,00 16,00   30,00   65,00
9,00   18,00   27,00 30,00   63,00 67,00
10,00   19,00   28,00 31,00   64,00 68,00
6,00 8,00   15,00 17,00   32,00   65,00 69,00
10,00   18,00   30,00 33,00   66,00 70,00
12,00   20,00   34,00   70,00 74,00
13,00   16,00 18,00   36,00   75,00
7,00 9,00   19,00   32,00 35,00   73,00 77,00
9,60   20,00   38,00   75,00 80,00
10,40   17,00 19,00   34,00 37,00   80,00 85,00
7,75 9,75   20,00   38,00   85,00 90,00


  • ID - inner diameter
  • OD - outer diameter


Outer diameter
Wall thickness
Roundness Deflection
6-15 +/- 2,0 % +/- 10% 10% 1,50% 2,5 mm
15 -20 +/- 1,5 % +/- 10% 15% 1,50% 2,5 mm
20 -25 +/- 1,5 % +/- 10% 15% 1,50% 3,0 mm
25-40 +/- 1,5 % +/- 15% 15% 1,50% 3,0 mm
40-60 +/- 1,5 % +/- 15% 15% 1,50% 3,0 mm
60 -80 +/- 1,5 % +/- 15% 15% 1,50% 3,0 mm

While every attempt has been made to verify the source of the information, no responsibility is accepted for accuracy of data.

Information clause

What personal data are processed and who is their administrator?

When using our services, personal data that we process may be, for example, the IP address of your device, data obtained from cookies or similar mechanisms for recording information in Users' devices, as long as they allow you to identify you. More information about the scope of personal data and cookies can be found in the Cookies policy and in Privacy policy.

Administrator, ie the entity deciding on which personal data will be processed and for what purpose, and in what way, is Continental Trade Sp. z o.o. (hereinafter "Continental Trade" or "We") with its registered office and address in Warsaw at Krasnobrodzka Street 5.

What is the purpose and basis of the processing of your personal data by Continental Trade ?

Continental Trade processes your personal data to enable you to use our services, match the displayed content and ads to your interests, measure quality and effectiveness, improve content and services.

The basis for the processing of personal data is the legitimate interest of Continental Trade. It includes improving services, ensuring their best quality and informing Users about them.

Confirming that you have read this information,   by clicking on "Go to website" or closing this window at the same time you agree that your personal data will be processed in the same way as described here. You can manage your consent, including withdrawal.

Providing personal information is voluntary.

What are your rights to   Continental Trade in terms of processed data?

You can request from Continental Trade: access to data, rectification, deletion, transfer and, in some cases, processing restrictions, and you have the right to object to the processing of your personal data when personal data are processed on the basis of the legitimate interest of the administrator. You have the right to file a complaint regarding the processing of your personal data to the President of the Office of Personal Data Protection.

To whom does Continental Trade share your personal data?

Continental Trade, in principle, does not share your personal data with third parties, except for situations in which Continental Trade has a legal basis, including at the request of authorized entities, or when it is necessary to perform services offered by Continental Trade, e.g. entrepreneurs providing hosting of our services.

How long does Continental Trade store your personal data?

Continental Trade stores Users' personal data only for the time that is necessary to achieve the purposes for which the data was collected and provided that one of the legal grounds described above is up-to-date or when a new ground has appeared, e.g. a law or the need to enforce claims in court proceedings.

Who can you contact for more information on the processing of personal data by Continental Trade?

If you have questions related to the processing of your personal data on websites operated by Continental Trade or would like to report the issue related to the processing of personal data by Continental Trade, you can contact a Continental Trade representative using the contact information:

More information on the protection of your personal data can be found in the Cookie Policy and Security Policy documents published on our website