Parshas Vayakhel begins by briefly mentioning the laws of Shabbos and then proceeds to the main theme of the Parsha, the construction of the mishkan (tabernacle).  Moses assembles the entire nation of Israel and lists the raw materials that G-d has instructed them to use.  The Jewish People donate everything that is needed.  The nesi'im (princes), who had committed to giving anything after the people’s donations, could only contribute the precious stones of the Kohen Gadol's (high priest’s) choshen (breastplate).  G-d instructs that two gifted craftsmen carry out the construction: Bezalel from the tribe of Yehuda, and Aliav from the tribe of Dan.  The Torah then describes the precise design and composition of many items in the Mishkan.