Why is this the answer?

The answer is icicle because this fun riddle uses beautiful and clever word pictures to describe a special kind of ice sculpture you often see hanging from roofs and branches during the cold winter months. It breaks down perfectly into clues that tell you exactly what it is. Let's look closely at the first line of the riddle: "Glittering points that downward thrust." This part is describing the icicle's appearance and its position. When the sun shines, the ice is clear and bright, which makes it "glitter." The word "points" refers to the sharp, narrow shape that icicles naturally form as water drips and freezes repeatedly. The phrase "downward thrust" is a very descriptive way of saying that the pointy tip of the icicle is always facing straight toward the ground, hanging from above because of gravity. Next, the riddle gives us more detail: "Sparkling spears that never rust." Icicles look exactly like miniature 'spears,' which are long, sharp tools from ancient times. They are called "sparkling" again because the clear, smooth ice catches the light and twinkles. The most important clue is "that never rust." Rust is a brownish-red color that only appears when metal gets wet and starts to break down. Since an icicle is made entirely of frozen water, it is not metal and cannot rust. Instead, when the temperature gets warm, the icicle simply melts away, proving it is not a rusty metal object. This poem beautifully captures the fragile, gleaming nature of the icicle, a temporary piece of natural art that only appears in the freezing cold.