中文：

稀土是一类珍贵的战略性资源，其全称为“稀土金属元素”（Rare Earth Elements）。它们在自然界中以稀有矿物形式存在，具有独特的光、电、磁、热等物理和化学特性，被广泛应用于高科技领域，如军工、航空航天、电子、新能源等。

稀土元素共有17种，包括镧（La）、铈（Ce）、镨（Pr）、钕（Nd）、钷（Pm）、钐（Sm）、铕（Eu）、钆（Gd）、铽（Tb）、镝（Dy）、钬（Ho）、铒（Er）、铥（Tm）、镱（Yb）、镥（Lu）。这些元素在地壳中的丰度很低，且分布不均匀。中国是世界上最主要的稀土生产国之一，拥有世界上最丰富的稀土资源。

稀土在许多高科技领域中发挥着关键作用。例如，稀土元素可以改善金属的机械性能和热稳定性，被广泛应用于航空航天、军工等领域的制造过程中。此外，稀土元素还被用于制造永磁体、发光材料、催化剂等重要产品。

然而，随着稀土资源的日益消耗和环境问题的不断凸显，稀土开采和生产面临着越来越大的挑战。因此，保护稀土资源、推动稀土产业可持续发展已成为全球关注的焦点。

英文：

Rare earths are a group of precious strategic resources, also known as "rare earth metal elements" (Rare Earth Elements). They exist in nature as rare minerals and have unique physical and chemical properties such as light, electricity, magnetism, and heat. They are widely used in high-tech fields such as military, aerospace, electronics, and new energy.

There are 17 rare earth elements, including lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), and lutetium (Lu). These elements have low abundance in the Earth's crust and are unevenly distributed. China is one of the world's largest rare earth producers and has the world's most abundant rare earth resources.

Rare earths play a key role in many high-tech fields. For example, rare earth elements can improve the mechanical properties and thermal stability of metals and are widely used in the manufacturing process of aviation, aerospace, and military industries. In addition, rare earth elements are also used in the manufacture of permanent magnets, luminescent materials, catalysts and other important products.

However, with the increasing consumption of rare earth resources and the constantly emerging environmental issues, rare earth extraction and production are facing increasing challenges. Therefore, protecting rare earth resources and promoting sustainable development of the rare earth industry have become global focuses.