I’m a day late on this article, but some will undoubtedly be interested anyway. From Arutz-7:
The Temple Institute will begin building the sacrificial altar on Thursday, Tisha B’av, a fast day when Jews mourn the destruction of the Temple some 2,000 years ago. The sacrificial altar was located in the center of the Temple, and upon it the Kohanim (priests) offered the numerous voluntary and obligatory sacrifices commanded in the Bible. The Temple Institute, which has already built many of the vessels for the Holy Temple, such as the ark and the menorah, has now embarked on a project to build the altar. Construction begins Thursday in Mitzpe Yericho (east of Jerusalem) at 5:30 p.m. “Unfortunately, we cannot currently build the altar in its proper place, on the Temple Mount,” Temple Institute director Yehudah Glick said. “We are building an altar of the minimum possible size so that we will be able to transport it to the Temple when it is rebuilt." Even a minimum size altar will work out to be approximately 2 meters tall, 3 meters long, and 3 meters wide. Workers have collected around 10 cubic meters of rocks weighing several tons already. The rocks were gathered from the Dead Sea area and wrapped individually to assure they remain whole and are not touched by metal, as the Bible requires. “The Torah says that no iron tools should be used on the altar’s stones,” Glick explained. “The altar represents a connection to life and to the creation of the world. Iron is the opposite – it is used to build tools of war, death, and destruction.”
The story continues here and includes a photo, a video, and an illustration.