Period 6 element years and is used in medical applications, industrial gauges, and hydrology. Although the element is only mildly toxic, it is a hazardous material as a metal and its radioisotopes present a high health risk in case of radioactivity releases. Barium is a chemical element with the symbol Ba and atomic number 56. It is the fifth element in Group 2, a soft silvery metallic alkaline earth metal. Barium is never found in nature in its pure form due to its reactivity with air. Its oxide is historically known as baryta but it reacts with water and carbon dioxide and is
Heart (symbol) but the "hearts" suit did not have this element since the 15th century. The heart symbol reached Japan with the Nanban trade of 1543 to 1614, as evidenced by an Edo period Samurai helmet (dated c. 1630), which includes both the rounded and indented forms of the heart symbol, representing the heart of Marishiten, goddess of archers. Since the 19th century, the symbol has often been used on Valentine's Day cards, candy boxes, and similar popular culture artifacts as a symbol of romantic love. The use of the heart symbol as a logograph for the English verb "to love" derives