Tweed pattern

Partially ordered K-feldspars (such as orthoclase, adularia, and intermediate microcline) characteristically exhibit a tweed pattern consisting... 

Tweed twinning. When impurity concentrations are sufficiently large, twin walls are stabilized and thus twin wall densities can be extremely high. As a result, mean twin domain sizes can decrease dramatically for relatively small concentrations of solute. In some instances, the twin walls adopt a characteristic checkerboard-like microstructure known as a tweed pattern with orthogonal modulations of -100-200 A. The formation and energetics of tweed twins are discussed in Chapter 3 of this volume by Salje and also in Putnis and Salje (1994) and Salje (1999). Examples of compositionally induced tweed textures include the doped superconductor YBa2(Cui-jcM f)307.8 for M = Co and Fe (Van Tendeloo et al 1987, Schmahl et al 1989, Xu et al. 1989) as well as As-doped lead phosphate (Bismayer et al. 1995) and Sr-doped anorthite (Tribaudino et al. 1995). Diffraction patterns of twin tweeds exhibit characteristic cross-shaped intensities superimposed on the primary spots. 

Twins and tweed pattern due to strains in the orthorhombic phase. 

Commercial fabrics made from sheep s wool have a variety of names, depending on the weave pattern and the weight of the fabric. These include cavalry twill, challis, felt, flannel, gabardine, khaki, tweed, serge, sharkskin, velour. Cassimere is a fabric made of sheep s wool, not cashmere. It is of moderate weight and used most often for making men s suits. 

Figure 8.26. BF image (and its associated selected area diffraaion pattern) showing the tweed microstructure in orthoclase. The shortest wavelength of the modulation is about 4.5 nm. (From McLaren and Fitz Gerald 1987.)...

In the middle of the nineteenth century the company developed a successful business producing Estate Tweeds . Estate Tweeds are a derivative of tartans . Tartan is a distinctive plaid traditionally worn by Scottish highlanders to denote their clan. The patterns of Estate Tweeds were specific to an individual estate -an estate being a (usually) large house or castle with significant land attached. The people who worked on that estate would often wear clothes made from the... 

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