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Studies of strategic mineral deposits in the major domestic pegmatite districts by the U. S. Geological Survey from 1939 to 1945, primarily for the purpose of increasing production of mica, beryllium, lithium, and tantalum minerals, resulted in the clarification of many problems related to the general. features, internal structure, mineralogy, and origin of granitic pegmatites. This report summarizes about 68 man years of work in the pegmatite districts of New England, the Southeastern States, South Dakota, Idaho, Montana, Wyoming, Colorado, and New Mexico. The pegmatites of eastern United States, of Paleozoic age, and those of the Rocky Mountain region, mostly of pre-Cambrian age, are localized in metamorphic terranes, and are closely associated with either granite, quartz monzonite, or granodiorite masses. In some districts where pegmatites are associated with all three types of igneous rocks the composition of the plagioclase feldspar in three separate groups of pegmatites suggests a genetic relationship to the three types of igneous rocks. In other districts the distribution of pegmatites suggests a genetic relationship to the adjacent igneous mass. Consequently the mineralogy, texture, and structure of the pegmatites varies in detail from district to district, though within any one district variations as great or greater may be found as the parent igneous rock is approached. Pegmatites range from a few inches to more than a mile in length, and from a fraction of an inch to more than 500 feet in width. Most are tabular or thinly lenticular; others are branching, irregular, or teardrop-shaped. Pipelike, arcuate, and troughlike forms are less common. The shapes of pegmatites commonly are closely controlled by the type and structure of the wall rock. Many pegmatites in schistose rocks are concordant with regional foliation, and plunge parallel to the linear structure of the schist. The plunge of discordant bodies is commonly controlled by the intersection of fractures. Secondary foliation and drag folds indicate deformation, of the wall rocks by the pegmatites during emplacement. Alteration of schistose country rocks to granulites is most common along the contacts of discordant bodies. The structural and lithologic units that differ in mineralogy, texture, or both have been designated as: (1) fracture filling– tabular units that fill fractures in previously consolidated pegmatite, (2) replacement bodies— units formed primarily by replacement of pre-existing pegmatite, and (3) zones —successive shells, complete or incomplete, around an innermost unit or core that reflect to varying degrees the shape and structure of the pegmatite body. Zones, quantitatively and economically the most important, have been classified as (1) border zones, (2) wall zones, (3) intermediate zones, and (4) cores.

Calligraphy is the art of writing characters with a brush and ink. Yet, the word “calligraphy,” from the Greek kalligraphía (beautiful writing), is something of a mistranslation of the Chinese term shufa (書法), which means “model writing,” or writing that is good enough to serve as a model. Calligraphy has no referent in nature, so all writing is modeled on that of another. Traditional calligraphers were less interested in mere beauty than in the ability of the gesture and the line to create images of aesthetic power and movement and in the paramount issue of upon whose writing they were modeling theirs. The precise moment Chinese characters were born is unknown, but a fully developed system was in use by c. 1200 bce, as seen on scripts on the incised oracle bones (jiaguwen甲骨文) and inscriptions cast into ritual bronze vessels (guwen古文) of the Shang dynasty. Over the next millennium, five major script types evolved. The archaic scripts gave way to the “large” seal script (zhuan篆) of the Zhou dynasty and the “small” seal script of the Qin. In Qin the clerical script (li隸) came into being and flourished during the succeeding Han, whereas by the end of the 2nd century the modern script types of regular (kai楷 or zhen真), running (xing行), and cursive (cao草) all had developed. Seal and clerical were relegated to decorative and monumental functions until they were revived as antiquarian modes in later times. Although mythic names are associated with the creation of each script type, there were no signed works of calligraphy until the Han dynasty. Since that time, when it began to be seen as expressive of its writer’s personality and character, calligraphy has been accorded the supreme position among the arts. Calligraphers could practice their art purely for their own pleasure or self-expression, or their work could be done for payment or in exchange for goods and services. Calligraphy had a rich tradition until the 20th century, and after China’s turmoil ended in the late 1970s, the amateur scene burgeoned again. In the late 20th century, Chinese calligraphy made a place for itself in the international art world, particularly through the incorporation of nonsense characters in multimedia installations. Critical texts that assessed famous calligraphers appeared in the 4th century, and histories of calligraphy have been written continually from the 5th century to the early 21st century. Japanese scholars have produced excellent research in the 20th and early 21st centuries, and researchers in the West have been writing on calligraphy history since the 1970s.

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