روايت شاهنامه بر جام سفالين بيژن و منيژه

Shahnama narrative on the pot; a case of Bijan and Manijeh

زرين فام، تشكيل لايه بسيار نازكي از نانو ذرات مس و نقره با جلاي فلزي در طيف هاي رنگي گوناگون است كه بر روي لعاب در سومين مرحله پخت در شرايط احيا كوره ايجاد مي گردد. اگر چه اين تكنيك در حوزه سفال ايران بسيار مهم بوده است اما متون معدودي در رابطه با آن از دوره هاي مختلف بر جاي مانده است. كتاب «جواهر نامه نظامي» تاليف محمد بن ابي البركات نيشابوري، يكي از اين متون، بعنوان قديمي ترين سند تاريخي درباره ساخت ميناي زرين فام مي باشد. در كتاب فوق فرمول هاي متعددي براي ساخت زرين فام ارايه شده است. اما سوال اساسي اين است كه آيا هنوز مي توان با تكيه بر همان فرمولها به لعاب زرين فام دست يافت؟ در مقاله حاضر با رويكردي تجربي، جهت بررسي صحت فرمولهاي ارايه شده در كتاب، يكي از فرمولها كه بنا به نظر نويسنده آن، تلالوي طلايي، مانند زر دارد به عنوان نمونه انتخاب و مورد آزمايش قرار گرفته است. نتايج آزمايشات گواه آن است كه فرمول ارايه شده بدون كم و كاست مي تواند ما را به ساخت لعاب زرين فام برساند. روش پژوهش ارزيابي است و با استفاده از تكنيك مشاهده و آزمون تجربي انجام يافته است.

Luster glaze technique is, in fact, using luster glaze in painting and decorating on the glaze which is heated in reduced kiln as a third step. Luster glaze is formation of a very thin layer of silver and copper nanoparticles with a metallic luster in different color range formed on the surface of the glaze during the third stage of heating in reduction condition. Luster glazed art’s peak, in Iran and the city of Kashan, was 6 until 8 centuries AH (12 until 14th). Although this technique has been a principle one in pottery making, a few texts from different periods have been left about it. Javaher name-ye- Nezami by Mohammad- ibn Abi-al-Barakat Juhari- Nishaboori is the earliest historical documents on Luster glaze which has various formulas for making it. Javaher Name-ye- Nezami was written in the year 592 AH (1195th). That seems to be not only the oldest work, but undoubtedly the most detailed written work on the sophisticated technology of luster glaze (until the 19th century). However, the key question is, whether one can still produce luster glaze based on these formulas. In the present study, by using an experimental approach, we verify the accuracy of one the formulas presented in this book. We chose a formula, which according to the writer of the book, produces glitter and golden luster. The research method is evaluation and it has been done through observation and experiment. The results show that the formula presented in Javaher- Name-ye- Nezami are quite capable of preparing Luster glaze. Material used in the formulas by Juhari- Nishaboori, are called by names which were common in the past and are unfamiliar to us today. Thus, to build the combinations suggested in the book, it is essential to have the equivalent of raw materials and their chemical compounds. Therefore, the modern day equivalences of the material were used. The material, following the formula, were weighted, mixed with vinegar and grounded for 30 minutes. Then, they were tested on proper alkaline glaze in different reduction condition. Alkaline glaze has been made semi-opaque by tin oxide and used as a base glaze. The result of Javaher- Name-ye- Nezami formula with the above mentioned combination was formation of a layer of luster glaze with metallic luster and golden sparkle. The result was achieved through reduction at Five hundred and eighty degrees centigrade (580° C) for about Seventy (70) minutes and four stages of wood burning. The results of the present research showed that in order to produce luster glaze it is essential to consider carefully the different parameters that effect luster glaze such as the base glaze, combination of glaze and condition of reduction. Proper reduction is very important during the process; therefore, every kiln will need different reduction condition based on its internal dimension, vents and type of the fuel it uses. The results show that if the proper conditions and various factored are considered, the formulas presented in Javaher- Name-ye- Nezami are quite capable of producing Luster glaze.